Method and apparatus for tricuspid valve repair using tension

ABSTRACT

Apparatus is provided including a first tissue-engaging element, a first flexible longitudinal member coupled at a first end portion thereof to at least a portion of the first tissue-engaging element, and a first flexible-longitudinal-member-coupling element coupled to the first flexible longitudinal member at a second end portion of the first flexible longitudinal member. Apparatus includes a second tissue-engaging element, a second flexible longitudinal member coupled at a first end portion thereof to at least a portion of the second tissue-engaging element, and a second flexible-longitudinal-member-coupling element coupled to the second flexible longitudinal member at a second end portion of the second flexible longitudinal member, the first and second flexible-longitudinal-member-coupling elements being couplable to couple together the first and second flexible longitudinal elements. Other applications are also described.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application:

(a) claims the priority from and is a continuation-in-part of U.S.patent application Ser. No. 13/188,175, filed Jul. 21, 2011, which is acontinuation-in-part of PCT application PCT/IL2011/00064, filed Jan. 20,2011, entitled, “Tricuspid valve repair using tension,” which claimspriority from and is a continuation-in-part of U.S. application Ser. No.12/692,061, filed Jan. 22, 2010, entitled, “Tricuspid valve repair usingtension;” and

(b) is related to a PCT application entitled: “Method and apparatus fortricuspid repair using tension,” filed on even date herewith.

All of these applications are incorporated herein by reference.

FIELD OF THE APPLICATION

Some applications of the present invention relate in general to valverepair. More specifically, some applications of the present inventionrelate to repair of a tricuspid valve of a patient.

BACKGROUND OF THE APPLICATION

Functional tricuspid regurgitation (FTR) is governed by severalpathophysiologic abnormalities such as tricuspid valve annulardilatation, annular shape, pulmonary hypertension, left or rightventricle dysfunction, right ventricle geometry, and leaflet tethering.Treatment options for FTR are primarily surgical. The current prevalenceof moderate-to-severe tricuspid regurgitation is estimated to be 1.6million in the United States. Of these, only 8,000 patients undergotricuspid valve surgeries annually, most of them in conjunction withleft heart valve surgeries.

SUMMARY OF THE INVENTION

In some applications of the present invention, apparatus and methods areprovided for repairing an atrioventricular valve of a patient usingtension. Typically, the apparatus and methods for repairing theatrioventricular valve facilitate reducing of atrioventricular valveregurgitation by altering the geometry of the atrioventricular valveand/or by altering the geometry of the wall of the right or left atriaof the heart of the patient. In some applications of the presentinvention, a first tissue-engaging element is implantable at a firstimplantation site in a vicinity of the atrioventricular valve of thepatient. A second tissue-engaging element is then implantable at asecond implantation site in a second portion of tissue that is upstreamof the atrioventricular valve of the patient (e.g., in a blood vesselthat empties into an atrium of the heart of the patient). Eachtissue-engaging element is coupled to respective first and secondlongitudinal members, which are couplable together using first andsecond longitudinal-member coupling elements. The first tissue-engagingelement is coupled to the tissue in the vicinity of the atrioventricularvalve of the patient, and the first longitudinal member is extendedtherefrom. The second tissue-engaging element is then delivered towardthe valve. The second longitudinal-member coupling element is coupled tothe first longitudinal-member coupling element, the secondtissue-engaging element is pulled toward the implantation site and thesecond longitudinal member is extended toward the second implantation.The second tissue engaging element is then deployed in the secondimplantation site upstream of the valve. Typically, as the secondlongitudinal member is extended by pulling on the second tissue-engagingelement, it pulls on and applies tension to the first longitudinalmember. Responsively, a distance between the leaflets of theatrioventricular valve is adjusted prior to implanting the secondtissue-engaging element. Alternatively or additionally, followingimplantation of both the first and second tissue-engaging elements, thedistance between the leaflets of the tricuspid valve is adjusted bypulling the first and second longitudinal members that connect the firstand second tissue-engaging elements or by pulling at least one of thetissue-engaging elements. For some applications, the first and secondlongitudinal members are coupled at least in part to an adjustingmechanism, and the first and second longitudinal members are pulled orrelaxed responsively to actuation of the adjusting mechanism. In someapplications, a delivery tool is provided which facilitates implantationof the first and second tissue-engaging elements.

In some applications of the present invention, a first tissue-engagingelement is implanted in a first portion of tissue that is upstream ofthe tricuspid valve of the patient. A second tissue-engaging element isthen implanted in a second portion of tissue that is upstream of thetricuspid valve of the patient. Typically, a distance between theleaflets of the tricuspid valve is adjusted by pulling on and applyingtension to the longitudinal member responsively to pulling on the secondtissue-engaging element prior to implanting the second tissue-engagingelement. Alternatively or additionally, following implantation of boththe first and second tissue-engaging elements, the distance between theleaflets of the tricuspid valve is adjusted by pulling a longitudinalmember that connects the first and second tissue-engaging elements or bypulling at least one of the tissue-engaging elements. For someapplications, the longitudinal member is coupled at least in part to anadjusting mechanism, and the longitudinal member is pulled or relaxedresponsively to actuation of the adjusting mechanism. In someapplications, a delivery tool is provided which facilitates implantationof the first and second tissue-engaging elements.

For some applications, apparatus described herein are used to repair thetricuspid valve. It is to be noted, however, that the scope of thepresent invention includes use of apparatus described herein to repairthe mitral valve of the patient, mutatis mutandis.

In some applications of the present invention, apparatus and method areprovided to achieve bicuspidization of the tricuspid valve. For suchapplications, typically, the anterior leaflet and the septal leaflet aredrawn together to enhance coaptation.

For some applications, the first tissue-engaging element comprises atissue anchor (e.g., a helical tissue anchor) which is implanted in aportion of tissue surrounding an annulus of the tricuspid valve (e.g.,an anterior-posterior commissure). Typically, the second tissue-engagingelement comprises a stent which is expanded in a portion of a bloodvessel of a patient, e.g., the superior vena cava, the inferior venacava, coronary sinus, or a hepatic vein, e.g., the left hepatic vein,the right hepatic vein, or the middle hepatic vein. During the adjustingof the distance between the first and second tissue-engaging elements,the physician monitors a parameter indicative of regurgitation of thetricuspid valve. Responsively to the pulling of the longitudinalelement(s), the geometry of the right atrium is altered, thereby drawingtogether the leaflets of the tricuspid valve.

It is to be noted that for some applications of the present invention,the first tissue-engaging element comprises a second stent which isexpanded in a portion of a second blood vessel of the patient, e.g., thesuperior vena cava, the inferior vena cava, the coronary sinus, or ahepatic vein, e.g., the left hepatic vein, the right hepatic vein andthe middle hepatic vein.

For some applications, a plurality of second tissue-engaging elementsare provided (such as two or three), which are implanted in respectiveportions of cardiac tissue in a vicinity of the heart valve. For someapplications, a longitudinal member is (a) directly coupled to the firsttissue-engaging element, (b) directly coupled to one of the secondtissue-engaging elements, and (c) indirectly coupled to two others ofthe second tissue-engaging elements by a longitudinal sub-member.

For still other applications of the present invention, both the firstand second tissue-engaging elements comprise respective first and secondtissue anchors. Each tissue anchor punctures a respective portion ofcardiac tissue of the patient and is implanted at least in part in therespective portion of cardiac tissue. The tensioning element couples thefirst and second tissue anchors and is adjusted following implantationof the first and second tissue anchors by pulling or relaxing thetensioning element.

For some applications of the present invention, a torque-delivering toolis provided for rotating a tissue anchor, so as to drive the anchor intotissue. The torque-delivering tool comprises a torque-delivering cable,a distal end of which comprises a first coupling that is configured toremovably engage a second coupling coupled to the anchor in a controlledmanner, such that rotation of the torque-delivering cable rotates theanchor. For some applications, the apparatus further comprises ananti-entanglement device which prevents entanglement of the flexiblelongitudinal member during rotation of the anchor.

For some applications, the stents described hereinabove comprise aplurality of interconnected superelastic metallic struts. For someapplications, the stents described herein comprise a force-distributingelement providing means to connect the stent to the flexible member anddistribute tension applied from the flexible member to the stent along alongitudinal length of the stent.

There is therefore provided, in accordance with some applications of thepresent invention, apparatus, including:

a radially-expandable percutaneous implant;

a tissue anchor having a central longitudinal axis;

a connecting element shaped so as to provide an annular loop surroundinga proximal portion of the tissue anchor in a manner which enablesrotation of the anchor about the central longitudinal axis whensurrounded by the annular loop; and

a flexible longitudinal member coupled at a first portion thereof to atleast a portion of the percutaneous implant and at a second portion tothe connecting element, the annular loop of the connecting elementfacilitating rotation of the tissue anchor about the centrallongitudinal axis such that the anchor can rotate about the centrallongitudinal axis with respect to the annular loop, the flexiblelongitudinal member, and the percutaneous implant.

In some applications of the present invention, the longitudinal memberincludes a plurality of fibers.

In some applications of the present invention, the plurality of fibersare arranged such that the longitudinal member has a length of between10 mm and 300 mm, a width of between 1 and 4 mm, and a thickness ofbetween 1 and 2 mm.

In some applications of the present invention, the plurality of fibersare arranged such that the longitudinal member has a length of between20 mm and 80 mm, a width of between 1 and 4 mm, and a thickness ofbetween 1 and 2 mm.

In some applications of the present invention, the plurality of fibersare interwoven so as to form a fabric.

In some applications of the present invention, the apparatus includes:

a tube, which is sized to pass through a lumen defined by thepercutaneous implant, the tube having at least one tube lumen, and

a torque-delivering tool configured for slidable passage through thetube, the torque-delivering tool is configured to be removably coupledto the tissue anchor, such that rotation of the torque-delivering toolrotates the tissue anchor.

In some applications of the present invention, the apparatus includes asheath configured to surround the percutaneous implant such that thepercutaneous implant is maintained in a crimped state when the sheathsurrounds the implant, and the sheath is slidable with respect to thetube in order to expose the implant from within the sheath.

In some applications of the present invention, the apparatus includes asecondary tube through which a guidewire may be passed, the secondarytube being configured to be disposed alongside the tube surrounding thetorque-delivering tool, the guidewire being configured to facilitateguiding of the apparatus through vasculature of a patient.

In some applications of the present invention:

the connecting element is shaped so as to define aflexible-longitudinal-member-coupler at a proximal portion thereof thatis proximal to the annular loop,

the flexible-longitudinal-member-coupler is coupled to the secondportion of the flexible longitudinal member, and

the torque-delivering tool passes alongside the flexible longitudinalmember in a manner which restricts entanglement of the flexiblelongitudinal member during rotation of the torque-delivering tool torotate the anchor.

In some applications of the present invention, the apparatus includes ananti-entanglement device coupled to the tube at a distal portionthereof, the anti-entanglement device is configured to restrictentanglement of the flexible longitudinal member during (1) rotation ofthe torque-delivering tool to rotate the anchor, and (2) rotation of theanchor with respect to the surrounding annular loop of the connectingelement.

In some applications of the present invention, the anti-entanglementdevice is configured to be disposed adjacently to theflexible-longitudinal-member-coupler in a manner which restrictsentanglement of the flexible longitudinal member during rotation of thetorque-delivering tool to rotate the anchor.

In some applications of the present invention, the apparatus includes:

the torque-delivering tool includes a first coupling at a distal endthereof, and

the apparatus further includes an adapter head coupled to the tissueanchor at a proximal end of the tissue anchor, the adapter headincluding a second coupling reversibly couplable to the first couplingin a manner which:

-   -   (1) couples the tissue anchor to the torque-delivering tool when        the first and second couplings are coupled together, and    -   (2) decouples the tissue anchor from the torque-delivering tool        when the first and second couplings are not coupled together.

In some applications of the present invention, the first couplingincludes a male coupling, the second coupling includes a femalecoupling, and the first and second couplings are couplable together bybeing matingly engaged.

In some applications of the present invention, when the distal end ofthe tool is surrounded by the tube, the first and second couplings aredisposed within the tube and are engaged, and the tool is slidablewithin the tube so as to expose the distal end of the tool and the firstand second couplings from within the tube in order to facilitatedisengaging of the couplings.

In some applications of the present invention, the apparatus includes aproximal handle portion coupled to a proximal portion of the tube, thehandle portion including:

a holder having a recess, the holder being coupled to a proximal portionof the tube, and

an anchor-deployment actuator including a proximal knob and a distalprotrusion slidable within the recess of the holder:

-   -   the anchor-deployment actuator is coupled to a proximal portion        of the torque-delivering tool,    -   the torque-delivering tool is slidable within the tube,    -   the anchor-deployment actuator is rotatable to rotate the        torque-delivering tool and the anchor, and    -   during a pushed state of the anchor-deployment actuator, the        protrusion slides distally within the recess of the holder, and        responsively, the torque-delivering tool is pushed distally to        expose the first and second couplings from within the tube and        disengage the first and second couplings.

In some applications of the present invention, the apparatus includes asafety coupled to the holder configured to prevent unwanted slidingdistally of the protrusion of the anchor-deployment actuator within therecess of the holder.

In some applications of the present invention, at least a proximalportion of the tissue anchor is shaped so as to define an opening and apassage therethrough, and the adapter head is shaped so as to define adistal protrusion sized so as to fit within the passage, therebycoupling the adapter head to the tissue anchor.

In some applications of the present invention:

a portion of the adapter head that is between the distal protrusion andthe second coupling is shaped so as to define a longest dimension at afirst cross-sectional plane that is perpendicular to the central axis ofthe tissue anchor,

the annular loop of the connecting element is shaped so as to define alongest dimension a second cross-sectional plane that is perpendicularto the central axis of the tissue anchor, and

the proximal portion of the adapter head is disposed coaxiallyproximally to the annular loop along the longitudinal axis in a mannerwhich restricts decoupling of the connecting element from the tissueanchor.

In some applications of the present invention, the percutaneous implantis shaped so as to define a tension-distributing element, and the firstportion of the flexible longitudinal element is coupled to thepercutaneous implant via the tension-distributing element.

In some applications of the present invention, the tension-distributingelement and the percutaneous implant are fabricated from a single unit.

In some applications of the present invention, the tension-distributingelement is configured to distribute tension applied by the flexiblelongitudinal member along a longitudinal length of the percutaneousimplant.

In some applications of the present invention, the tension-distributingelement has a width of between 1 and 4 mm.

In some applications of the present invention, the percutaneous implantincludes a stent including a plurality of struts, and a width of awidest strut is between 100 and 500 micron, and a width of thetension-distributing element is between 1 and 4 mm.

In some applications of the present invention, the percutaneous implantincludes an endoluminal implant including a stent including a pluralityof struts, and a width of the tension-distributing element is at least13 times a width of a widest strut of the stent.

In some applications of the present invention, a longitudinal length ofthe tension-distributing element is at least 15% of the longitudinallength of the percutaneous implant.

In some applications of the present invention, the longitudinal lengthof the percutaneous implant is between 20 and 120 mm, and thelongitudinal length of the tension-distributing element is between 10and 120 mm.

In some applications of the present invention, the percutaneous implantincludes an endoluminal implant including a stent.

In some applications of the present invention, a first section of thestent includes two or more coaxial annular ring portions, each ringportion shaped so as to define a plurality of peaks and valleys, and thefirst section includes a plurality of interconnectors configured toconnect the two or more annular ring portions.

In some applications of the present invention:

the two or more coaxial annular ring portions include first and secondannular ring portions that are in phase, and

each one of the plurality of interconnectors is disposed verticallybetween a respective valley of the first and second ring portions.

In some applications of the present invention:

the stent is configured to assume a compressed state within a sheath andan expanded state when exposed from within the sheath by retracting thesheath in a distal-to-proximal direction,

each one of the valleys of the first annular ring portion is connectedby a respective interconnector to a respective valley of the secondannular ring portion, and

each one of the peaks points in a distal direction in a manner in which,following expansion of the first and second annular ring portions fromwithin a sheath, the first and second annular ring portions arecompressible and retrievable into the sheath when the sheath is advancedin a proximal-to-distal direction.

In some applications of the present invention, the stent is shaped so asto define a first section configured, in a radially-expanded state ofthe stent, to exert a stronger radial force on surrounding tissue than asecond section of the stent.

In some applications of the present invention, the first and secondportions are each shaped so as to define respective wire structures,each wire structure including a respective plurality of wire segments,and each wire segment of the second portion has a length greater than alength of a respective wire segment of the first portion.

In some applications of the present invention, the first and secondportions are each shaped so as to define respective wire structures,each wire structure including a respective plurality of wire segments,and each wire segment of the first portion has a thickness greater thana thickness of a respective wire segment of the second portion.

In some applications of the present invention, each wire segment of thefirst portion has a thickness of between 50 and 1000 micron, and eachwire segment of the second portion has a thickness of between 50 and1000 micron.

In some applications of the present invention, the first sectionincludes two or more coaxial annular ring portions, each ring portionshaped so as to define a plurality of peak and valleys, and the firstsection includes a plurality of interconnectors configured to connectthe two or more annular ring portions.

In some applications of the present invention:

the two or more coaxial annular ring portions include first and secondannular ring portions that are in phase, and

each one of the plurality of interconnectors is disposed verticallybetween a respective valley of the first and second ring portions.

In some applications of the present invention:

the stent is configured to assume a compressed state within a sheath andan expanded state when exposed from within the sheath by retracting thesheath in a distal-to-proximal direction,

each one of the valleys of the first annular ring portion is connectedby a respective interconnector to a respective valley of the secondannular ring portion, and

each one of the peaks points in a distal direction in a manner in which,following expansion of the first and second annular ring portions fromwithin a sheath, the first and second annular ring portions arecompressible and retrievable into the sheath when the sheath is advancedin a proximal-to-distal direction.

In some applications of the present invention, the second sectionincludes a plurality of vertical elements extending from the firstportion.

In some applications of the present invention, the vertical elementseach have a length of between 10 and 80 mm.

In some applications of the present invention, the stent is shaped so asto define a third portion configured, in the radially-expanded state ofthe stent, to exert a stronger radial force on surrounding tissue thanthe second section of the stent.

There is further provided, in accordance with some applications of thepresent invention, a method, including:

providing (a) a radially-expandable percutaneous implant, (b) tissueanchor having a central longitudinal axis, (c) a connecting elementshaped so as to provide an annular loop surrounding a proximal portionof the tissue anchor in a manner which enables rotation of the anchorabout the central longitudinal axis when surrounded by the annular ring,and (d) a flexible longitudinal member, which has a first portion thatis coupled to at least a portion of the percutaneous implant and asecond portion that is coupled to the connecting element;

positioning the percutaneous implant in a blood vessel of a patient;

coupling the tissue anchor to tissue in a vicinity of a heart valve ofthe patient by rotating the anchor with respect to the annular loop, thelongitudinal member, and the percutaneous implant; and

after coupling the tissue anchor to the tissue, deploying thepercutaneous implant such that the implant expands and is implanted inthe blood vessel at an implantation site.

In some applications of the present invention, the method includes,after coupling the tissue anchor to the tissue and before deploying thepercutaneous implant, pulling the anchor toward the implantation site.

In some applications of the present invention, the blood vessel isselected from the group of blood vessels consisting of: a superior venacava, an inferior vena cava, a coronary sinus, and a hepatic vein.

In some applications of the present invention, rotating includesrotating the anchor using a tube, which passes through a lumen definedby the stent, and which is removably coupled to the tissue anchor.

There is additionally provided, in accordance with some applications ofthe present invention, a method, including:

providing (a) a radially-expandable percutaneous implant, (b) tissueanchor having a central longitudinal axis, (c) a connecting elementshaped so as to provide an annular loop surrounding a proximal portionof the tissue anchor in a manner which enables rotation of the anchorabout the central longitudinal axis when surrounded by the annular ring,and (d) a flexible longitudinal member, which has a first portion thatis coupled to at least a portion of the percutaneous implant and asecond portion that is coupled to the connecting element; and

rotating the anchor with respect to the annular loop, the longitudinalmember, and the percutaneous implant while restricting rotation of theflexible longitudinal member.

There is yet additionally provided, in accordance with some applicationsof the present invention, apparatus including:

a radially-expandable percutaneous implant shaped so as to define atension-distributing element; and

a flexible longitudinal member coupled at a first portion thereof to atleast a portion of the percutaneous implant via the tension-distributingelement, the tension-distributing element is configured to distributetension applied by the flexible longitudinal member along a longitudinallength of the percutaneous implant.

In some applications of the present invention, the apparatus includes atissue anchor coupled to the flexible longitudinal member at a secondportion thereof, the tissue anchor and the flexible longitudinal memberbeing configured to apply tension to the tension-distributing element.

In some applications of the present invention, the tension-distributingelement and the percutaneous implant are fabricated from a single unit.

In some applications of the present invention, the tension-distributingelement has a width of between 1 and 4 mm.

In some applications of the present invention, the percutaneous implantincludes a stent including a plurality of struts, and a width of awidest strut is between 100 and 500 micron and a width of thetension-distributing element is between 1 and 4 mm.

In some applications of the present invention, the percutaneous implantincludes a stent including a plurality of struts, and a width of thetension-distributing element is at least 13 times a width of a wideststrut of the stent.

In some applications of the present invention, a longitudinal length ofthe tension-distributing element is at least 15% of the longitudinallength of the percutaneous implant.

In some applications of the present invention, the longitudinal lengthof the percutaneous implant is between 20 and 120 mm, and thelongitudinal length of the tension-distributing element is between 10and 120 mm.

In some applications of the present invention, the percutaneous implantincludes an endoluminal implant including a stent.

In some applications of the present invention, a first section of thestent includes two or more coaxial annular ring portions, each ringportion shaped so as to define a plurality of peaks and valleys, and thefirst section includes a plurality of interconnectors configured toconnect the two or more annular ring portions.

In some applications of the present invention:

the two or more coaxial annular ring portions include first and secondannular ring portions that are in phase, and

each one of the plurality of interconnectors is disposed verticallybetween a respective valley of the first and second ring portions.

In some applications of the present invention:

the stent is configured to assume a compressed state within a sheath andan expanded state when exposed from within the sheath by retracting thesheath in a distal-to-proximal direction,

each one of the valleys of the first annular ring portion is connectedby a respective interconnector to a respective valley of the secondannular ring portion, and

each one of the peaks points in a distal direction in a manner in which,following expansion of the first and second annular ring portions fromwithin a sheath, the first and second annular ring portions arecompressible and retrievable into the sheath when the sheath is advancedin a proximal-to-distal direction.

In some applications of the present invention, the stent is shaped so asto define a first section configured to exert a stronger radial force onsurrounding tissue than a second section of the stent.

In some applications of the present invention, the first and secondportions are each shaped so as to define respective wire structures,each wire structure including a respective plurality of wire segments,each wire segment of the second portion has a length greater than alength of a respective wire segment of the first portion.

In some applications of the present invention, the first and secondportions are each shaped so as to define respective wire structures,each wire structure including a respective plurality of wire segments,each wire segment of the first portion has a thickness greater than athickness of a respective wire segment of the second portion.

In some applications of the present invention, each wire segment of thefirst portion has a thickness of between 100 and 1000 micron, and eachwire segment of the second portion has a thickness of between 100 and1000 micron.

In some applications of the present invention, the first sectionincludes two or more coaxial annular ring portions, each ring portionshaped so as to define a plurality of peak and valleys, and the firstsection includes a plurality of interconnectors configured to connectthe two or more annular ring portions.

In some applications of the present invention:

the two or more coaxial annular ring portions include first and secondannular ring portions that are in phase,

each one of the plurality of interconnectors is disposed verticallybetween a respective valley of the first and second ring portions.

In some applications of the present invention:

the stent is configured to assume a compressed state within a sheath andan expanded state when exposed from within the sheath by retracting thesheath in a distal-to-proximal direction,

each one of the valleys of the first annular ring portion is connectedby a respective interconnector to a respective valley of the secondannular ring portion, and

each one of the peaks points in a distal direction in a manner in which,following expansion of the first and second annular ring portions fromwithin a sheath, the first and second annular ring portions arecompressible and retrievable into the sheath when the sheath is advancedin a proximal-to-distal direction.

In some applications of the present invention, the second sectionincludes a plurality of vertical elements extending from the firstportion.

In some applications of the present invention, the vertical elementseach have a length of between 10 and 60 mm.

In some applications of the present invention, the stent is shaped so asto define a third portion configured to exert a stronger radial force onsurrounding tissue than the second section of the stent.

There is also provided, in accordance with some applications of thepresent invention, apparatus, including:

a first radially-expandable percutaneous implant including a pluralityof mechanical structural elements arranged so as to assume a firsttubular structure, the first radially-expandable percutaneous implant,in a radially-expanded state thereof, having a lumen having an innerdiameter;

a flexible longitudinal member coupled at a first portion thereof to atleast a portion of the first radially-expandable percutaneous implant,the flexible longitudinal member being configured to apply tension tothe first radially-expandable percutaneous implant; and

a second radially-expandable percutaneous implant positionable withinthe lumen of the first radially-expandable percutaneous implant, thesecond radially-expandable percutaneous implant:

including a plurality of mechanical structural elements arranged so asto assume a second tubular structure,

being shaped so as to define a plurality of tissue-engaging elementsconfigured to engage tissue of a patient in a radially-expanded state ofthe second radially-expandable percutaneous implant,

in the radially-expanded state thereof, being configured to:

-   -   excluding the plurality of tissue-engaging elements, assume an        outer diameter of the second radially-expandable percutaneous        implant that is at least as large as the inner diameter of the        first radially-expandable percutaneous implant in the        radially-expanded state of the first radially-expandable        percutaneous implant, and    -   provide anchoring of the first radially-expandable percutaneous        implant in the radially-expanded state, to tissue of the patient        by facilitating engaging of the plurality of tissue-engaging        elements with the tissue of the patient in the radially-expanded        state of the second radially-expandable percutaneous implant.

In some applications of the present invention, the apparatus includes atissue anchor coupled to the flexible longitudinal member at a secondportion thereof, the tissue anchor and the flexible longitudinal memberbeing configured to apply tension to the tension-distributing element.

In some applications of the present invention, the plurality oftissue-engaging elements include a plurality of barbs.

In some applications of the present invention, in the radially-expandedstate of the second radially-expandable percutaneous implant, the secondradially-expandable percutaneous implant pushes radially against thefirst radially-expandable percutaneous implant.

There is further provided, in accordance with some applications of thepresent invention, a method, including:

positioning a first radially-expandable percutaneous implant in a bloodvessel of a patient, the first radially-expandable percutaneous implantincluding a plurality of mechanical struts arranged so as to assume afirst tubular structure, the first radially-expandable percutaneousimplant, in a radially-expanded state thereof, having a lumen having aninner diameter;

applying tension to the first radially-expandable percutaneous implant;

while tension is applied to the first radially-expandable percutaneousimplant, expanding the first radially-expandable percutaneous implant inthe blood vessel in a manner in which the first radially-expandablepercutaneous implant exerts a radial force on the blood vessel; and

anchoring the first radially-expandable percutaneous implant to theblood vessel by expanding a second radially-expandable percutaneousimplant within the lumen of the first radially-expandable percutaneousimplant, the second radially-expandable percutaneous implant including aplurality of mechanical struts arranged so as to assume a second tubularstructure, and by the expanding, engaging a plurality of tissue-engagingelements of the second radially-expandable percutaneous implant withtissue of the blood vessel.

In some applications of the present invention, expanding the secondradially-expandable percutaneous implant includes expanding the secondradially-expandable percutaneous implant in a manner in which the secondradially-expandable percutaneous implant, excluding the plurality oftissue-engaging elements, assumes an outer diameter that is at least aslarge as the inner diameter of the first radially-expandablepercutaneous implant in the radially-expanded state of the firstradially-expandable percutaneous implant.

In some applications of the present invention, prior to expanding thesecond radially-expandable percutaneous implant, allowing migrationwithin the blood vessel of the first radially-expandable percutaneousimplant.

In some applications of the present invention, engaging the plurality oftissue-engaging elements of the second radially-expandable percutaneousimplant with tissue of the blood vessel includes preventing migration ofthe first radially-expandable implant within the blood vessel.

There is additionally provided, in accordance with some applications ofthe present invention, apparatus, including:

a first tissue-engaging element;

a first flexible longitudinal member coupled at a first end portionthereof to at least a portion of the first tissue-engaging element;

a first flexible-longitudinal-member-coupling element coupled to thefirst flexible longitudinal member at a second end portion of the firstflexible longitudinal member;

a second tissue-engaging element;

a second flexible longitudinal member coupled at a first end portionthereof to at least a portion of the second tissue-engaging element; and

a second flexible-longitudinal-member-coupling element coupled to thesecond flexible longitudinal member at a second end portion of thesecond flexible longitudinal member, the first and secondflexible-longitudinal-member-coupling elements being couplable to coupletogether the first and second flexible longitudinal elements.

In some applications of the present invention, at least a portion of thefirst tissue-engaging element is shaped so as to define a loop, andwherein the first end portion of the first flexible longitudinal memberis configured to be looped at least in part around the loop of the firsttissue-engaging element.

In some applications of the present invention, the apparatus includes aconnecting element coupled to the first tissue-engaging element, theconnecting element shaped so as to provide an annular loop surrounding aproximal portion of the first tissue-engaging element in a manner whichenables rotation of the anchor about the central longitudinal axis whensurrounded by the annular loop, wherein the annular loop of theconnecting element facilitates rotation of the first tissue-engagingelement about a central longitudinal axis of the first tissue-engagingelement such that the first tissue-engaging element can rotate about thecentral longitudinal axis with respect to the annular loop and the firstflexible longitudinal member.

In some applications of the present invention, the apparatus includes aflexible-longitudinal-member-adjustment mechanism coupled to a flexiblelongitudinal member selected from the group consisting of: the firstflexible longitudinal member and the second flexible longitudinalmember, and wherein the flexible-longitudinal-member-adjustmentmechanism is configured to adjust a length of the selected flexiblelongitudinal member.

In some applications of the present invention, theflexible-longitudinal-member-adjustment mechanism includes a spoolconfigured to adjust a length of the selected flexible longitudinalmember by winding a portion of the selected flexible longitudinal memberaround the spool.

In some applications of the present invention, the first tissue-engagingelement includes a tissue anchor configured to penetrate tissue of anannulus of an atrioventricular valve of a patient.

In some applications of the present invention, the secondtissue-engaging element includes a radially-expandable percutaneousimplant configured to engage tissue of the patient upstream of theatrioventricular valve.

In some applications of the present invention, the radially-expandablepercutaneous implant includes a stent configured for placement within ablood vessel that empties into an atrium of a heart of the patient.

In some applications of the present invention, the tissue anchorincludes a helical tissue anchor, and wherein the apparatus furtherincludes a torque-delivering tool configured to corkscrew the helicaltissue anchor into tissue of a patient.

In some applications of the present invention, the apparatus includes aconnecting element shaped to define an annular loop surrounding aproximal portion of the tissue anchor, in a manner which enablesrotation of the anchor about a longitudinal axis of the tissue anchor,when surrounded by the annular loop, and with respect to the firstflexible longitudinal member.

In some applications of the present invention:

the apparatus further includes a first coupling element coupled to thefirst tissue-engaging element, the first coupling element having afirst-coupling-element longitudinal axis and shaped so as to define:

-   -   a first-coupling-element main body portion shaped so as to        define a first-coupling-element-main-body passage,    -   a first-coupling-element secondary body portion coaxial with the        first-coupling-element main body portion, the first-coupling        element secondary body portion shaped so as to define a        first-coupling-element-secondary-body-portion passage coaxial        with the first-coupling-element-main-body passage; and    -   a connecting element connecting the first-coupling-element        secondary body portion to the first-coupling-element main body        portion,

the first coupling element is shaped so as to define afirst-coupling-element space between the first-coupling-element mainbody portion and the first-coupling-element secondary body portion,

the apparatus further includes a second coupling element having asecond-coupling-element longitudinal axis and shaped so as to define:

-   -   a second-coupling-element main body portion shaped so as to        define second-coupling-element-main-body passage,    -   a second-coupling-element secondary body portion coaxial with        the main body portion, the second-coupling-element secondary        body portion shaped so as to define a        second-coupling-element-secondary-body-portion passage coaxial        with the second-coupling-element-main-body passage, and    -   a connecting element connecting the second-coupling-element        secondary body portion to the second-coupling-element main body        portion,

the second coupling element is shaped so as to define asecond-coupling-element space between the main body portion and thesecondary body portion, and

the first and second coupling elements are couplable together by fittingthe first-coupling-element secondary body portion within thesecond-coupling-element space of the second coupling element, and byfitting the second-coupling-element secondary body portion within thefirst-coupling-element space of the first coupling element in a mannerin which the first-coupling-element-main-body passage, thefirst-coupling-element-secondary-body-portion passage, thesecond-coupling-element-main-body passage, and thesecond-coupling-element-secondary-body-portion passage are aligned, and

the apparatus further includes an elongate longitudinal element:

-   -   disposable within the first-coupling-element-main-body passage,        the first-coupling-element-secondary-body-portion passage, the        second-coupling-element-main-body passage, and the        second-coupling-element-secondary-body-portion passage to        maintain coupling of the first coupling element to the second        coupling element, and    -   removable from the first-coupling-element-main-body passage, the        first-coupling-element-secondary-body-portion passage, the        second-coupling-element-main-body passage, and the        second-coupling-element-secondary-body-portion passage to        facilitate decoupling of the first and second coupling elements.

In some applications of the present invention, the elongate longitudinalelement includes a rod.

In some applications of the present invention, thefirst-coupling-element main body portion is shaped so as to define acylinder.

In some applications of the present invention, thesecond-coupling-element main body portion is shaped so as to define acylinder.

In some applications of the present invention, the firstflexible-longitudinal-member-coupling element includes a male coupling,and the second flexible-longitudinal-member-coupling element includes afemale coupling configured to receive the male coupling.

In some applications of the present invention, the female coupling isshaped so as to define one or more grooves, and wherein the malecoupling is shaped so as to provide one or more protrusions configuredto fit within the one or more grooves of the female coupling.

In some applications of the present invention:

the female coupling includes a cylinder configured to receive the malecoupling,

the female coupling is shaped so as to define one or more tabs biased toflex toward a longitudinal axis of the cylinder,

the male coupling is shaped so as to provide one or more protrusionsdefining a shelf,

the male coupling advanceable with respect to the one or more tabs in afirst direction to push the tab away from the longitudinal axis, and

the one or more tabs are configured to flex toward the longitudinal axisafter the advancement of the shelf of the male coupling beyond the oneor more tabs to restrict advancement of the male coupling in a seconddirection.

In some applications of the present invention,

the female coupling includes a structural element including one or morewalls shaped so as to define an opening,

the male coupling includes one or more radially-displaceable arms, and

the one or more radially-displaceable arms are:

-   -   compressible by the walls during advancement of the one or more        radially-displaceable arms through the opening, and    -   following advancement of the one or more radially-displaceable        arms through opening, expandable to a first dimension that is        larger than a second dimension of the opening so as to lock the        male coupling to the female coupling.

In some applications of the present invention,

the female coupling includes a structural element including one or morewalls shaped so as to define an opening,

the male coupling includes one or more radially-displaceable arms, and

the one or more radially-displaceable arms are:

-   -   compressible by the walls during advancement of the one or more        radially-displaceable arms through the opening, and    -   following advancement of the one or more radially-displaceable        arms through opening, expandable to a position in which at least        a portion of an outer surface of the one or more arms is beyond        and above the one or more walls.

In some applications of the present invention,

the female coupling includes a structural element including one or morewalls shaped so as to define one or more shelves,

the male coupling includes one or more radially-displaceable legs,

the one or more radially-displaceable legs are:

-   -   compressible by the walls during advancement of the one or more        radially-displaceable legs along the one or more shelves, and    -   following the advancement of the one or more        radially-displaceable legs beyond the one or more shelves in a        first advancement direction, expandable to

lock the male coupling to the female coupling, and

following expanding of the one or more radially-displaceable legs, theone or more shelves of the female coupling restrict advancement of theone or more radially-displaceable legs in a second advancementdirection.

In some applications of the present invention, the one or more walls ofthe female coupling element is shaped so as to define at least onegroove, and wherein the male coupling element is shaped so as to defineat least one protrusion shaped so as to fit within the at least onegroove.

In some applications of the present invention, the female couplingincludes a structural element shaped so as to define a curved groove,and wherein the male coupling includes a projection advanceable withinthe curved groove so as to lock the male coupling to the femalecoupling.

In some applications of the present invention, the apparatus furtherincludes a flexible longitudinal guide member reversibly coupled to thefirst flexible-longitudinal-member-coupling element.

In some applications of the present invention, the flexible longitudinalguide member is reversibly coupled to the firstflexible-longitudinal-member-coupling element by being looped through aportion of the first flexible-longitudinal-member-coupling element.

In some applications of the present invention:

the first flexible-longitudinal-member-coupling element is shaped so asto define a first coupling,

the flexible longitudinal guide member is reversibly coupled to thefirst flexible-longitudinal-member-coupling element via the firstcoupling, and

the flexible longitudinal guide member is configured to facilitateadvancement of the second flexible-longitudinal-member-coupling elementalong the guide member and toward the firstflexible-longitudinal-member-coupling element.

In some applications of the present invention, the apparatus includes asnare couplable to the flexible longitudinal guide member so as tofacilitate extraction of a portion of the guide member outside a body ofa patient.

In some applications of the present invention:

the first tissue-engaging element, the first flexible longitudinalmember, and the first flexible-longitudinal-member-coupling element areadvanceable within the body of that patient from a first site thereof,

the second tissue-engaging element, the second flexible longitudinalmember, and the second flexible-longitudinal-member-coupling element areadvanceable within the body of that patient from a second site thereof,and

the snare is configured to extend a portion of the flexible longitudinalguide member toward the second site.

In some applications of the present invention, the first couplingincludes a threaded coupling, and wherein the flexible longitudinalguide member is reversibly coupled to the first coupling by beingscrewed with respect to the threaded coupling.

In some applications of the present invention, the first coupling isshaped so as to define at least one shelf, and wherein the apparatusfurther includes a longitudinal-guide-member-coupling element, whereinthe longitudinal-guide-member-coupling element is:

coupled to the longitudinal guide member,

restricted from advancement in a first direction by the at least oneshelf, and

displaceable with respect to the at least one shelf in response to achange in a spatial orientation of thelongitudinal-guide-member-coupling element with respect to the at leastone shelf, and allowed to advance in the first direction in order todecouple the longitudinal guide member from the firstflexible-longitudinal-member-coupling element.

In some applications of the present invention:

the first flexible-longitudinal-member-coupling element has afirst-coupling-element longitudinal axis and wherein the first couplingis shaped so as to define:

-   -   a first-coupling-element main body portion shaped so as to        define first-coupling-element-main-body passage;    -   a first-coupling-element secondary body portion coaxial with the        main body portion, the first-coupling element secondary body        portion shaped so as to define a        first-coupling-element-secondary-body-portion passage coaxial        with the first-coupling-element-main-body passage; and    -   a connecting element connecting the secondary body portion to        the main body portion,

the first flexible-longitudinal-member-coupling element is shaped so asto define a first-coupling-element space between the main body portionand the secondary body portion,

the apparatus further includes a longitudinal-guide-member-couplingelement having a longitudinal-guide-member-coupling element longitudinalaxis and a second coupling, wherein the flexible longitudinal guidemember coupled to the longitudinal-guide-member-coupling element, and isreversibly coupled to the first flexible-longitudinal-member-couplingelement via the longitudinal-guide-member-coupling element, the secondcoupling being shaped so as to define:

-   -   a longitudinal-guide-member-coupling-element main body portion        shaped so as to define second-coupling-element-main-body        passage;    -   a longitudinal-guide-member-coupling-element secondary body        portion coaxial with the main body portion, the        longitudinal-guide-member-coupling-element secondary body        portion shaped so as to define a        longitudinal-guide-member-coupling        element-secondary-body-portion passage coaxial with the        longitudinal-guide-member-coupling-element-main-body passage;        and    -   a connecting element connecting the        longitudinal-guide-member-coupling-element secondary body        portion to the longitudinal-guide-member-coupling-element main        body portion,

the second coupling element is shaped so as to define asecond-coupling-element space between the main body portion and thesecondary body portion, and

the first and second couplings are couplable together by fitting thefirst-coupling-element secondary body portion within thelongitudinal-guide-member-coupling-element space of the second couplingelement, and by fitting the longitudinal-guide-member-coupling-elementsecondary body portion within the first-coupling-element space of thefirst coupling element in a manner in which thefirst-coupling-element-main-body passage, thefirst-coupling-element-secondary-body-portion passage, thelongitudinal-guide-member-coupling-element-main-body passage, and thelongitudinal-guide-member-coupling-element-secondary-body-portionpassage are aligned.

In some applications of the present invention, the apparatus furtherincludes an elongate longitudinal element:

disposable within the first-coupling-element-main-body passage, thefirst-coupling-element-secondary-body-portion passage, thelongitudinal-guide-member-coupling-element-main-body passage, and thelongitudinal-guide-member-coupling-element-secondary-body-portionpassage to maintain coupling of the first and second couplings, and

removable from the first-coupling-element-main-body passage, thefirst-coupling-element-secondary-body-portion passage, thelongitudinal-guide-member-coupling-element-main-body passage, and thelongitudinal-guide-member-coupling-element-secondary-body-portionpassage to facilitate decoupling of the first and second couplings.

There is yet additionally provided, in accordance with some applicationsof the present invention a method, including:

implanting a first tissue-engaging element at a first implantation sitein tissue of an atrioventricular valve of a patient;

extending from the first tissue-engaging element, a first flexiblelongitudinal member coupled at a first end portion thereof to at least aportion of the first tissue-engaging element, the first flexiblelongitudinal element being coupled at a second end portion thereof to afirst flexible-longitudinal-member-coupling element;

advancing toward the valve of the patient a second tissue-engagingelement coupled to a first end portion of a second flexible longitudinalmember, the second flexible longitudinal member being coupled at asecond end portion thereof to a secondflexible-longitudinal-member-coupling element;

coupling together the first and secondflexible-longitudinal-member-coupling elements;

facilitating repairing of the atrioventricular valve by pulling on thesecond tissue-engaging element, and responsively, pulling on the firstand second flexible longitudinal members; and

implanting the second tissue-engaging element at a second implantationsite upstream of the atrioventricular valve.

In some applications of the present invention, facilitating repairingincludes remodeling the atrioventricular valve by drawing togetherleaflets of the valve responsively to the pulling.

There is still yet additionally provided, in accordance with someapplications of the present invention, apparatus including:

a first coupling element having a first-coupling-element longitudinalaxis and shaped so as to define:

-   -   a first-coupling-element main body portion shaped so as to        define first-coupling-element-main-body passage;    -   a first-coupling-element secondary body portion coaxial with the        first-coupling-element main body portion, the first-coupling        element secondary body portion shaped so as to define a        first-coupling-element-secondary-body-portion passage coaxial        with the first-coupling-element-main-body passage; and    -   a first-coupling-element connecting element connecting the        first-coupling-element secondary body portion to the        first-coupling-element main body portion,

wherein the first coupling element is shaped so as to define afirst-coupling-element space between the first-coupling-element mainbody portion and the first-coupling-element secondary body portion;

a second coupling element having a second-coupling-element longitudinalaxis and shaped so as to define:

-   -   a second-coupling-element main body portion shaped so as to        define second-coupling-element-main-body passage;    -   a second-coupling-element secondary body portion coaxial with        the second-coupling-element main body portion, the        second-coupling-element secondary body portion shaped so as to        define a second-coupling-element-secondary-body-portion passage        coaxial with the second-coupling-element-main-body passage; and    -   a second-coupling-element connecting element connecting the        second-coupling-element secondary body portion to the        second-coupling-element main body portion,

wherein:

-   -   the second coupling element is shaped so as to define a        second-coupling-element space between the        second-coupling-element main body portion and the        second-coupling-element secondary body portion, and    -   the first and second coupling elements are couplable together by        fitting the first-coupling-element secondary body portion within        the second-coupling-element space of the second coupling        element, and by fitting the second-coupling-element secondary        body portion within the first-coupling-element space of the        first coupling element in a manner in which the        first-coupling-element-main-body passage, the        first-coupling-element-secondary-body-portion passage, the        second-coupling-element-main-body passage, and the        second-coupling-element-secondary-body-portion passage are        aligned; and an elongate longitudinal element:    -   disposable within the first-coupling-element-main-body passage,        the first-coupling-element-secondary-body-portion passage, the        second-coupling-element-main-body passage, and the        second-coupling-element-secondary-body-portion passage to        maintain coupling of the first coupling element to the second        coupling element, and    -   removable from the first-coupling-element-main-body passage, the        first-coupling-element-secondary-body-portion passage, the        second-coupling-element-main-body passage, and the        second-coupling-element-secondary-body-portion passage to        facilitate decoupling of the first and second coupling elements.

In some applications of the present invention, the elongate longitudinalelement includes a rod.

In some applications of the present invention, thefirst-coupling-element main body portion is shaped so as to define acylinder.

In some applications of the present invention, thesecond-coupling-element main body portion is shaped so as to define acylinder.

In some applications of the present invention, the first couplingelement is coupled to a tissue anchor and wherein the second couplingelement is coupled to a tissue-anchor-delivering tool.

In some applications of the present invention, the tissue anchorincludes a helical tissue anchor, and wherein thetissue-anchor-delivering tool includes a torque-delivering toolconfigured to corkscrew the helical tissue anchor into tissue of apatient.

In some applications of the present invention, the torque-deliveringtool is coupled to the second coupling element.

In some applications of the present invention, the apparatus includes aconnecting element shaped to define an annular loop surrounding aproximal portion of the first coupling element, in a manner whichenables rotation of the anchor and the first coupling element about thefirst-coupling-element longitudinal axis, when surrounded by the annularloop.

In some applications of the present invention, the apparatus includes aflexible, longitudinal band coupled to the connecting element, whereinthe tissue anchor and the first coupling element are configured torotate with respect to the flexible, longitudinal band.

There is further provided, in accordance with some applications of thepresent invention, a method, including:

providing a first coupling element having a first-coupling-elementlongitudinal axis and shaped so as to define:

-   -   a first-coupling-element main body portion shaped so as to        define first-coupling-element-main-body passage;    -   a first-coupling-element secondary body portion coaxial with the        main body portion, the first-coupling element secondary body        portion shaped so as to define a        first-coupling-element-secondary-body-portion passage coaxial        with the first-coupling-element-main-body passage; and    -   a connecting element connecting the secondary body portion to        the main body portion,

wherein the first coupling element is shaped so as to define afirst-coupling-element space between the main body portion and thesecondary body portion;

providing a second coupling element having a second-coupling-elementlongitudinal axis and shaped so as to define:

-   -   a second-coupling-element main body portion shaped so as to        define second-coupling-element-main-body passage;    -   a second-coupling-element secondary body portion coaxial with        the main body portion, the second-coupling element secondary        body portion shaped so as to define a        second-coupling-element-secondary-body-portion passage coaxial        with the second-coupling-element-main-body passage; and    -   a connecting element connecting the secondary body portion to        the main body portion,

wherein the second coupling element is shaped so as to define asecond-coupling-element space between the main body portion and thesecondary body portion;

coupling together the first and second coupling elements are couplabletogether by fitting the first-coupling-element secondary body portionwithin the second-coupling-element space of the second coupling element,and by fitting the second-coupling-element secondary body portion withinthe first-coupling-element space of the first coupling element in amanner in which the first-coupling-element-main-body passage, thefirst-coupling-element-secondary-body-portion passage, thesecond-coupling-element-main-body passage, and thesecond-coupling-element-secondary-body-portion passage are aligned;

maintaining the coupling by inserting an elongate longitudinal elementwithin the first-coupling-element-main-body passage, thefirst-coupling-element-secondary-body-portion passage, thesecond-coupling-element-main-body passage, and thesecond-coupling-element-secondary-body-portion passage to maintaincoupling of the first coupling element to the second coupling element;and

facilitating decoupling of the first and second coupling elements byremoving the elongate longitudinal element.

In some applications of the present invention, the elongate longitudinalelement includes a rod.

In some applications of the present invention, the method includesproviding a tissue anchor coupled to the first coupling element, andproviding a tissue-anchor-delivery tool coupled to the second element.

In some applications of the present invention, the tissue anchorincludes a helical tissue anchor, and wherein the tissue-anchor-deliverytool includes a torque-delivering tool configured to deliver torque tothe tissue anchor to corkscrew the helical tissue anchor into tissue ofa patient.

In some applications of the present invention, corkscrewing the helicaltissue anchor includes rotating the first coupling element and theanchor about the first-coupling-element longitudinal axis, and whereinrotating includes rotating the first coupling element and the anchorwith respect to a connecting element coupled to an annular loopsurrounding a proximal portion of the first coupling element.

In some applications of the present invention, rotating includesrotating the first coupling element and the anchor with respect to aflexible, longitudinal band coupled to the connecting element.

There is also provided, in accordance with some applications of thepresent invention, apparatus including:

a first tissue-engaging element;

at least one flexible longitudinal member coupled at a first end portionthereof to at least a portion of the first tissue-engaging element;

a second tissue-engaging element including a stent, the secondtissue-engaging element being coupled to the first tissue-engagingelement via the at least one flexible longitudinal member; and

a flexible-longitudinal-member-adjustment mechanism coupled to the atleast one flexible longitudinal member, theflexible-longitudinal-member-adjustment mechanism being configured toadjust a length of the selected flexible longitudinal member to draw thefirst and second tissue-engaging elements toward each other.

In some applications of the present invention, theflexible-longitudinal-member-adjustment mechanism includes a spoolconfigured to adjust a length of the at least one flexible longitudinalmember by winding a portion of the at least one flexible longitudinalmember around the spool.

The present invention will be more fully understood from the followingdetailed description of applications thereof, taken together with thedrawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A-D are schematic illustrations of apparatus for reducingregurgitation of a heart valve which comprises a stent, a tissue anchor,and a tensioning element that couples the stent and the tissue anchor,in accordance with some applications of the present invention;

FIGS. 2A-B are schematic illustrations of apparatus for reducingregurgitation of the heart valve which comprises first and secondstents, first and second tissue anchor, and first and second tensioningelements, in accordance with some applications of the present invention;

FIGS. 3A-C are schematic illustrations of apparatus for reducingregurgitation of the heart valve which comprises a single stent, firstand second tissue anchor, and first and second tensioning elements, inaccordance with some applications of the present invention;

FIGS. 4A-C are schematic illustrations of apparatus for reducingregurgitation of a tricuspid valve which comprises first and secondstents and first and a tensioning element that couples the first andsecond stents, in accordance with some applications of the presentinvention;

FIGS. 5A-B are schematic illustrations of apparatus for reducingregurgitation of the heart valve which comprises two or three tissueanchors and a tensioning element that couples the tissue anchors, inaccordance with some applications of the present invention;

FIG. 6 is a schematic illustration of apparatus for reducingregurgitation of the heart valve which comprises a first anchoringsystem in the inferior vena cava, a first tissue anchor implanted at thevalve, and a second tissue anchor implanted in the papillary muscle;

FIGS. 7A-D are schematic illustrations of a delivery system for ahelical tissue anchor, in accordance with some applications of thepresent invention;

FIGS. 8 and 9 are schematic illustrations of a system for repairing atricuspid valve, using a superior vena cava approach and an inferiorvena cava approach, respectively, in accordance with respectiveapplications of the present invention;

FIGS. 10A-D are schematic illustrations of tissue anchors, in accordancewith respective applications of the present invention;

FIGS. 11A-C are schematic illustrations of another delivery system for ahelical tissue anchor, in accordance with some applications of thepresent invention;

FIGS. 12A-C are schematic illustrations of the release of the tissueanchor from the delivery system of FIGS. 11A-C, in accordance with someapplications of the present invention;

FIGS. 13A-C are schematic illustrations of a stent coupled to a helicalanchor, in accordance with some applications of the present invention;

FIGS. 14A-C are schematic illustrations of another stent coupled to ahelical anchor, in accordance with some applications of the presentinvention;

FIGS. 15A-B are schematic illustrations of yet another stent coupled toa helical anchor, in accordance with some applications of the presentinvention;

FIGS. 16A-B are schematic illustrations of a first and a second stentconfigured to be disposed concentrically, in accordance with someapplications of the present invention;

FIG. 17 is a schematic illustration of apparatus for reducingregurgitation of a heart valve which comprises a stent, a tissue anchor,and a tensioning element that couples the stent and the tissue anchor,in accordance with some applications of the present invention;

FIGS. 18A-B are schematic illustrations of an alternative portion of thedelivery system of FIGS. 11A-C, in accordance with some applications ofthe present invention;

FIG. 19 is a schematic illustration of an endoluminal implant coupled toa helical anchor, in accordance with some applications of the presentinvention;

FIGS. 20-26 are schematic illustrations of apparatus for reducingregurgitation of a heart valve which comprises a stent, a tissue anchor,and first and second flexible longitudinal members that couple the stentand the tissue anchor using respective coupling elements, in accordancewith some applications of the present invention;

FIG. 27 is a schematic illustration of aflexible-longitudinal-member-adjustment mechanism for adjusting a lengthof at least one of the first and second flexible longitudinal members ofFIGS. 20-26, in accordance with some applications of the presentinvention;

FIG. 28 is a schematic illustration of respective coupling elements ofthe first and second flexible longitudinal members of FIGS. 20-26, inaccordance with another application of the present invention;

FIGS. 29 and 30A-D are schematic illustrations of respective couplingelements of the first and second flexible longitudinal members of FIGS.20-26, in accordance with yet another application of the presentinvention;

FIG. 31 is a schematic illustration of respective coupling elements ofthe first and second flexible longitudinal members of FIGS. 20-26, inaccordance with still yet another application of the present invention;and

FIG. 32 is a schematic illustration of a flexible longitudinal guidemember reversibly coupled to one of the coupling elements of FIGS.20-31, in accordance with some applications of the present invention.

DETAILED DESCRIPTION OF APPLICATIONS

Reference is now made to FIGS. 1A-D, which are schematic illustrationsof a system 20 comprising a first tissue-engaging element 60 a and asecond tissue-engaging element 60 b for repairing a tricuspid valve 4 ofa heart 2 of a patient, in accordance with some applications of thepresent invention. First tissue-engaging element 60 a comprises a tissueanchor 40 which is designated for implantation at least in part incardiac tissue at a first implantation site 30. It is to be noted thattissue anchor 40 comprises a helical tissue anchor by way ofillustration and not limitation and that tissue anchor 40 may compriseany tissue anchor for puncturing or clamping cardiac tissue, including,but not limited to, the tissue anchors described hereinbelow withreference to FIGS. 7A-D, 10A-D 11A-C, 12A-C, 13A-C, and 14A-C. Secondtissue-engaging element 60 b comprises a percutaneous implant, forexample, an endoluminal implant, e.g., stent 50, which is designated forimplantation in a portion of a blood vessel, e.g., a superior vena cava10 (not shown) or an inferior vena cava 8 (such as shown in FIGS. 1A-D),at a second implantation site 52. First and second tissue-engagingelements 60 a and 60 b are coupled together by a flexible longitudinalmember 42. Typically, a distance between first and second implantationsites 30 and 52 is adjusted by pulling to apply tension to or relaxinglongitudinal member 42 and/or by applying tension to at least one offirst and second tissue-engaging elements 60 a and 60 b. Responsively, adistance between the leaflets of tricuspid valve 4 is adjusted to reduceand eliminate regurgitation through valve 4, and thereby, valve 4 isrepaired. For some applications, longitudinal member 42 is pulled orrelaxed by manipulating second tissue-engaging element 60 b, as isdescribed hereinbelow.

Typically, longitudinal member 42 comprises a flexible biocompatibletextile e.g. polyester, nylon, PTFE, ePTFE, PEEK, PEBAX™, and/orsuperelastic material, e.g., nitinol. Typically, longitudinal member 42comprises a plurality of fibers which are aligned, e.g., woven orintertwined, to form a fabric band, as will be described hereinbelowwith reference to FIGS. 11A-C, 13C, and 14C. In some applications of thepresent invention, longitudinal member 42 comprises a braided polyestersuture (e.g., DACRON™). In other applications of the present invention,longitudinal member 42 is coated with polytetrafluoroethylene (PTFE). Insome applications of the present invention, longitudinal member 42comprises a plurality of wires that are intertwined to form a ropestructure. For some applications, at least a part of longitudinal member42 comprises a tension spring and/or a plurality of coils.

For some applications, first and second tissue-engaging elements 60 aand 60 b and longitudinal member 42 are fabricated from the samematerial, e.g., nitinol, from a single piece. That is, first and secondtissue-engaging elements 60 a and 60 b and longitudinal member 42 definea single continuous implant unit. For some applications, at least secondtissue-engaging element 60 b and longitudinal member 42 are fabricatedfrom a single piece.

For some applications, second tissue-engaging element 60 b comprises astent 50 which is advanced toward and expandable in a portion ofinferior vena cava 8 (such as shown in FIGS. 1A-D) or superior vena cava10 (not shown), i.e., a blood vessel that is in direct contact with aright atrium 6 of heart 2 of the patient. Second tissue-engaging element60 b is implanted at second implantation site 52. As shown, firstimplantation site 30 comprises a portion of an annulus of tricuspidvalve 4, specifically the anteroposterior commissure by way ofillustration and not limitation. For some applications, implantationsite 30 typically comprises a portion of the annulus of valve 4 that isbetween (1) the middle of the junction between the annulus and anteriorleaflet 14, and (2) the middle of the junction between the annulus andposterior leaflet 16, e.g., between the middle of the junction betweenthe annulus and anterior leaflet 14 and the commissure between theanterior and posterior leaflets. That is, anchor 40 is coupled to, e.g.,screwed into, the fibrous tissue of the tricuspid annulus close to thecommissure in between anterior leaflet 14 and posterior leaflet 16.Implantation site 30 is typically close to the mural side of valve 4.For such applications, the drawing together of first and secondimplantation sites 30 and 52 cinches valve 4 and may create abicuspidization of tricuspid valve 4, and thereby achieve strongercoaptation between anterior leaflet 14 and septal leaflet 12. During thebicuspidization, posterior leaflet 16 may be offset outside the plane ofvalve 4.

For some applications, first implantation site 30 may include a portionof tissue of a wall defining right atrium 6 of heart 2, typically in avicinity of the annulus of valve 4, e.g., the anterior-posteriorcommissure, as shown. For other applications, first implantation site 30may include a portion of a wall of a right ventricle of heart 2, aventricular portion of the annulus of valve 4, or a portion of apapillary muscle of the right ventricle of heart 2, as is shownhereinbelow in FIG. 6. First implantation site 30 is typically adistance away from, e.g., generally opposite, second implantation site52 so that, following adjusting of longitudinal member 42, first andsecond implantation sites 30 and 52 are drawn together, and thereby atleast first and second leaflets, e.g., all three leaflets, of valve 4are drawn toward each other. For applications in which firstimplantation site 30 includes a portion of tissue of the annulus, theadjusting of the distance between implantation sites 30 and 52 altersthe geometry of (i.e., changes the configuration of) the annulus ofvalve 4 and thereby draws together the leaflets of valve 4. Forapplications in which first implantation site 30 includes tissue of aportion of a wall that defines atrium 6, the adjusting of the distancebetween implantation sites 30 and 52 alters the geometry of (i.e.,changes the configuration of) the wall of atrium 6 and thereby drawstogether the leaflets of valve 4.

FIG. 1A shows the advancement of a catheter 22 toward atrium 6 of thepatient until a distal end 23 of the catheter is disposed within atrium6, as shown. The procedure is typically performed with the aid ofimaging, such as fluoroscopy, transesophageal echo, and/orechocardiography. For some applications, the procedure begins byadvancing a semi-rigid guidewire into right atrium 6 of the patient. Theguidewire provides a guide for the subsequent advancement of a catheter22 therealong and into the right atrium. For some applications, oncedistal end 23 of catheter 22 has entered right atrium 6, the guidewireis retracted from the patient's body. Catheter 22 typically comprises a14-20 F sheath, although the size may be selected as appropriate for agiven patient. Catheter 22 is advanced through vasculature into rightatrium 6 using a suitable point of origin typically determined for agiven patient. For example:

-   -   catheter 22 may be introduced into the femoral vein of the        patient, through inferior vena cava 8, and into right atrium 6;    -   catheter 22 may be introduced into the basilic vein, through the        subclavian vein through superior vena cava 10, and into right        atrium 6; or    -   catheter 22 may be introduced into the external jugular vein,        through the subclavian vein through superior vena cava 10, and        into right atrium 6.

As shown in FIG. 1A, catheter 22 is advanced through inferior vena cava8 of the patient and into right atrium 6 using a suitable point oforigin typically determined for a given patient. Alternatively, catheter22 is advanced through superior vena cava 10 of the patient and intoright atrium 6 using a suitable point of origin typically determined fora given patient.

Once distal end 23 of catheter 22 is disposed within atrium 6, ananchor-deployment tube 24 is extended from within catheter 22 beyonddistal end 23 thereof and toward first implantation site 30.Anchor-deployment tube 24 holds tissue anchor 40 and a distal portion oflongitudinal member 42. For some applications, tube 24 is steerable, asis known in the catheter art, while for other applications, a separatesteerable element may be coupled to anchor-deployment tube 24. Under theaid of imaging guidance, anchor-deployment tube 24 is advanced towardfirst implantation site 30 until a distal end thereof contacts cardiactissue of heart 2 at first implantation site 30. Anchor-deployment tube24 facilitates atraumatic advancement of first tissue-engaging element60 a toward first implantation site 30. For such applications in whichanchor-deployment tube 24 is used, stent 50 is compressed within aportion of tube 24.

An anchor-manipulating tool (not shown for clarity of illustration),which is slidably disposed within anchor-deployment tube 24, is sliddistally within tube 24 so as to push distally tissue anchor 40 of firsttissue-engaging element 60 a and expose tissue anchor 40 from withintube 24, as shown in FIG. 1B. For some applications of the presentinvention, the anchor-manipulating tool is reversibly coupled to anchor40 and facilitates implantation of anchor 40 in the cardiac tissue. Forapplications in which anchor 40 comprises a helical tissue anchor, asshown, the operating physician rotates the anchor-manipulating tool froma site outside the body of the patient in order to rotate anchor 40 andthereby screw at least a portion of anchor 40 in the cardiac tissue.

Alternatively, system 20 is provided independently of theanchor-manipulating tool, and anchor-deployment tube 24 facilitatesimplantation of anchor 40 in the cardiac tissue. For applications inwhich anchor 40 comprises a helical tissue anchor, as shown, theoperating physician rotates anchor-deployment tube 24 from a siteoutside the body of the patient in order to rotate anchor 40 and therebyscrew at least a portion of anchor 40 in the cardiac tissue.

It is to be noted that for some applications of the present invention,anchor 40 comprises a clip, jaws, or a clamp which grips and squeezes aportion of cardiac tissue and does not puncture the cardiac tissue.

Following the implantation of anchor 40 at first implantation site 30,anchor-deployment tube 24 is retracted within catheter 22 in order toexpose longitudinal member 42, as shown in FIG. 1C. Subsequently,longitudinal member 42 is pulled taut in order to repair tricuspid valve4, as described hereinbelow.

For some applications, distal end 23 of catheter 22 is fixed in placewith respect to longitudinal member 42. Fixing in place catheter 22stabilizes catheter 22 as longitudinal member 42 is pulled. This enablesdistal end 23 to remain in place and not slide distally towardimplantation site 30 during the adjusting of longitudinal member 42. Forsome applications of the present invention, a proximal portion ofcatheter 22 and/or a proximal handle portion coupled to catheter 22 isanchored or otherwise fixed in place at its access location, e.g., bytaping or plastering. Alternatively or additionally, a distal portion ofcatheter 22 comprises an inflatable element coupled to an inflationconduit which runs the length of catheter 22 from the distal portionthereof to a site outside the body of the patient. Prior to theadjusting of longitudinal member 42, the inflatable element is inflatedsuch that it contacts tissue of the vasculature through which catheter22 is advanced, and thereby catheter 22 is fixed in place. Typically,the inflatable element comprises an annular inflatable element, suchthat when inflated, the annular inflatable element functions as a sealto hold in place the distal portion of catheter 22.

(In this context, in the specification and in the claims, “proximal”means closer to the orifice through which the implant (i.e., theprosthetic valve and the valve support) is originally placed into thebody of the patient, along the path of delivery of the implant, and“distal” means further from this orifice along the path of delivery ofthe implant.)

Following the fixation of the mechanism that facilitates pulling oflongitudinal member 42, the physician then pulls longitudinal member 42and thereby draws together first and second implantation sites 30 and52.

For some applications, catheter 22 is reversibly coupled to a proximalportion of longitudinal member 42 by being directly coupled to theproximal portion of member 42 and/or catheter 22 is reversibly coupledto second tissue-engaging element 60 b. For example, catheter 22 may bereversibly coupled to stent 50 by the stent's application of a radialforce against the inner wall of catheter 22 because of the tendency ofstent 50 to expand radially. Following implantation of firsttissue-engaging element 60 a, catheter 22 (or an element disposedtherein) is then pulled proximally to apply tension to longitudinalmember 42, which, in such an application, functions as a tensioningelement. For some applications, catheter 22 pulls on secondtissue-engaging element 60 b in order to pull longitudinal member 42.For other applications, catheter 22 pulls directly on longitudinalmember 42. For yet other applications, a pulling mechanism pulls onlongitudinal member 42, as is described hereinbelow with reference toFIGS. 7A-D.

Pulling longitudinal member 42 pulls taut the portion of longitudinalmember 42 that is disposed between anchor 40 and distal end 23 ofcatheter 22. Additionally, longitudinal member 42 may be pulled orrelaxed in order to adjust the distance between first and secondimplantation sites 30 and 52. Responsively to the pulling oflongitudinal member 42, at least the anterior and septal leaflets oftricuspid valve 4 are drawn together because the geometry of the annulusand/or of the wall of atrium 6 is altered in accordance with the pullingof longitudinal member 42 and depending on the positioning of firsttissue-engaging element 60 a. For some applications, during the pullingof longitudinal member 42 by catheter 22, a level of regurgitation oftricuspid valve 4 is monitored and a parameter indicative of repair ofvalve 4 is monitored. For example, leaflet anatomy during the openingand closing of valve 4 is assessed using an imaging device such asintracardiac echocardiography, transthoracic echocardiography ortransesophageal echocardiography. For some applications, during themonitoring, measurements used to assess the efficiency of the procedureare evaluated pre-, during, and post-procedure. For example, thesemeasurements could include, but not exclusively, measuring theechocardiographic distance between the anteroposterior commissure andthe rim at the junction of the inferior vena cava and the right atrium,or measuring the echocardiographic regurgitant volume through tricuspidvalve 4. Longitudinal member 42 is pulled until the regurgitation isreduced or ceases.

Once the physician determines that the regurgitation of valve 4 isreduced or ceases, and valve 4 has been repaired, the physiciandecouples catheter 22 from second tissue-engaging element 60 b disposedtherein and/or from longitudinal member 42, and then retracts catheter22 in order to expose second tissue-engaging element 60 b, i.e., stent50. During the advancement of catheter 22 toward atrium 6, stent 50 isdisposed within a distal portion of catheter 22 in a compressed state.Following initial retracting of catheter 22, stent 50 is exposed and isallowed to expand and contact a wall of inferior vena cava 8.Responsively to the expanding, stent 50 is implanted in secondimplantation site 52 and maintains the tension of longitudinal member 42on anchor 40 and thereby on the portion of cardiac tissue to whichanchor 40 is coupled.

Reference is again made to FIGS. 1A-D. For some applications, followingthe implantation of first and second tissue-engaging elements 60 a and60 b, a distance between first and second tissue-engaging elements 60 aand 60 b is adjusted by an adjustable mechanism, as describedhereinbelow with reference to FIGS. 5A-B. In such applications, a lengthof longitudinal member 42 between first and second tissue-engagingelements 60 a and 60 b may be adjusted by an adjusting mechanism 150, asshown in FIGS. 5A-B. Adjusting mechanism 150 typically comprises amechanical element which shortens a distance of longitudinal member 42between first and second tissue-engaging elements 60 a and 60 b. Forsome applications, adjustable mechanism 150 may be permanently coupledto longitudinal member 42 (not shown) and comprises an adjustingelement, e.g., a spool for looping portions of longitudinal member 42therearound, a crimping bead for crimping and shortening a portion oflongitudinal member 42, a ratchet element, or a deforming element whichdeforms a portion of longitudinal member 42 in order to shorten itslength between first and second tissue-engaging elements 60 a and 60 b.A level of regurgitation of valve 4 may be monitored during theadjusting of the distance between first and second tissue-engagingelements 60 a and 60 b by adjusting mechanism 150.

For some applications, such as shown in FIG. 1D, stent 50 comprises aplurality of interconnected superelastic metallic struts, arranged so asto allow crimping the stent into a relatively small diameter (typicallyless than 8 mm) catheter, while allowing deployment to a much largerdiameter (typically more than 20 mm) in the vena cava, while stillmaintaining radial force against the vena cava tissue, in order toanchor stent 50 to the wall of the vena cava by friction.

For some applications, such as those described with reference to FIGS.1A-D, longitudinal member 42 has a length of at least 10 mm, no morethan 40 mm, and/or between 10 and 40 mm.

The configuration of stent 50 that is shown in FIG. 1D deployed ininferior vena cava 8 may instead be deployed in superior vena cava 10(deployment not shown).

Reference is now made to FIGS. 7A-D, which are schematic illustrationsof a delivery tool system 200 for implanting anchor 40, in accordancewith some applications of the present invention. Delivery tool system200 may be used, for example, to rotate and implant an anchor incombination with the applications described herein with reference toFIGS. 1A-D, 2A-B, 3A-C, 5A-B, 6, 8, 9, 13A-C, 14A-C, 15A-B, 16A-B, and17. Although longitudinal member 42 is shown in FIGS. 7A-D as beingfixed to stent 50, this is not necessarily the case, and tool system 200thus may also be used in combination with the applications that do notutilize stent 50, such as those described herein with reference to FIGS.3C and 5A-B.

Reference is now made to FIGS. 1A-D and 7A-D. It is to be noted thatanchor 40 may be implanted using delivery tool system 200. FIG. 7A showsan exploded view of the components of delivery tool system 200 and itsspatial orientation relative to stent 50, longitudinal member 42, andanchor 40. In such an application, a distal end of longitudinal member42 comprises an annular loop 216, through which a portion of anchor 40is coupled to the distal end of longitudinal member 42. For some suchapplications, stent 50, longitudinal member 42, and anchor 40 are notfabricated from the same piece, as described hereinabove; rather, onlystent 50, longitudinal member 42, and annular loop 216 are typicallyfabricated from a single piece, and anchor 40 is coupled to longitudinalmember 42 via annular loop 216. Alternatively, as mentioned above,longitudinal member 42 is not coupled to stent 50, such as forapplications in which stent 50 is not provided.

System 200 typically comprises an adapter 218, which, for someapplications, is shaped so as to define an annular proximal portion anda distal cylindrical portion having a distal end 220. During themanufacture of system 200, distal end 220 of the cylindrical portion ofadapter 218 is slid through annular loop 218 at the distal end oflongitudinal member 42, thereby coupling adapter 218 to the distal endof longitudinal member 42. Distal end 220 of adapter 218 is then weldedor otherwise fixedly coupled to a proximal portion of an inner lumen ofanchor 40, as shown in FIG. 7B. This coupling arrangement of anchor 40to annular loop 216 and adapter 218 enables anchor 40 to rotate about acentral longitudinal axis of delivery system 200, freely within annularloop 216. That is, delivery tool system 200 rotates anchor 40 withoutrotating longitudinal member 42 and stent 50 (if provided), as describedhereinbelow.

Delivery tool system 200 comprises a delivery tool overtube 202 having adistal end thereof. For application in which stent 50 is provided,delivery tool overtube 202 is housed within catheter 22 such that adistal portion thereof passes in part through the lumen of stent 50 anda distal end 204 thereof extends toward tissue anchor 40. Duringdelivery of tissue anchor 40 and stent 50 toward their respectiveimplantation sites, deliver tool system 200 assumes the configurationshown in FIG. 7B. It is to be noted, however, that stent 50 iscompressed around the portion of overtube 202 that extends through thelumen of stent 50 (not shown for clarity of illustration), and thatcatheter 22 (not shown for clarity of illustration) surrounds system 200(and thereby compresses stent 50).

Reference is again made to FIG. 7A. Overtube 202 houses atorque-delivering and an anchor-pulling tube 208 and facilitatesslidable coupling of tube 208 to overtube 202. A distal end oftorque-delivering and anchor-pulling tube 208 is coupled to amanipulator 206 which is shaped so as to define a coupling 210 whichcouples manipulator 206 to adapter 218, and thereby, to anchor 40. Inorder to rotate anchor 40, torque-delivering and anchor-pulling tube 208is rotated. As torque-delivering and anchor-pulling tube 208 is rotated,manipulator 206 is rotated in order to screw anchor 40 into the cardiactissue of the patient. As adapter 218 rotates, the cylindrical portionthereof rotates freely within annular loop 216. This couplingarrangement of adapter 218 (and thereby anchor 40) to loop 216 (andthereby longitudinal member 42) enables the physician to rotate andimplant anchor 40 without rotating longitudinal member 42 and stent 50(if provided).

Following rotation of anchor 40, torque-delivering and anchor-pullingtube 208 is pulled by the physician in order to pull on anchor 40 andthereby on the portion of cardiac tissue to which anchor 40 is implantedat first implantation site 30. Tube 208 is typically coupled at aproximal end thereof to a mechanical element, e.g., a knob, at thehandle portion outside the body of the patient. The physician pulls ontube 208 by actuating the mechanical element that is coupled to theproximal end of tube 208. This pulling of tube 208, and thereby ofanchor 40 and of cardiac tissue at first implantation site 30, drawsfirst implantation site toward second implantation site 52 and therebydraws at least anterior leaflet 14 toward septal leaflet 12 in order toachieve coaptation of the leaflets and reduce regurgitation throughvalve 4.

For some applications in which stent 50 is provided, following thepulling of anchor 40, stent 50 is positioned at second implantation site52. Catheter 22 is then retracted slightly along tube 202 so as to pulltaut longitudinal member 42 and to ensure that tension is maintained atfirst implantation site 30 and along longitudinal member 42. Stent 50 isthen deployed when the physician holds torque-delivering andanchor-pulling tool 208 and then retracts proximally either (1) catheter22 or (2) a sheath (i.e., that is disposed within catheter 22 andsurrounds stent 50), around stent 50 so as to deploy stent 50 fromwithin either (1) catheter 22 or (2) the sheath disposed within catheter22.

It is to be noted that stent 50 is retrievable following at leastpartial deployment thereof, e.g., following deployment of up to ½ or upto ⅓ of stent 50. In such an application, following the initialretraction proximally of catheter 22 from around stent 50 in order todeploy at least a distal portion of stent 50, catheter 22 is advanceabledistally so as to compress and retrieve the at least partially-deployedstent back into the distal end portion of catheter 22. Alternatively,catheter 22 houses a sheath which compresses stent 50 during delivery ofstent to second implantation site 52. During the initial retracting ofcatheter 22 proximally, the sheath surrounding stent 50 is alsoretracted in conjunction with the retracting of catheter 22. Followingthe at least partial deployment of stent 50 in order to deploy at leasta distal portion of stent 50, the sheath is advanceable distally (whilecatheter 22 remains in place) so as to compress and retrieve the atleast partially-deployed stent back into the distal end portion of thesheath. The sheath is then retracted into catheter 22. For suchapplications of the present invention in which stent 50 is retrievablefollowing at least partial deployment thereof, anchor 40 can then beunscrewed from first implantation site 30 and the entire implant systemmay be extracted from the body, or repositioned in the heart, dependingon the need of a given patient.

For applications in which stent 50 is retrievable, in order to retrievestent 50 (i.e., prior to the decoupling of manipulator 206 from adapter218 and thereby from anchor 40), the physician holds torque-deliveringand anchor-pulling tool 208 and then advances distally either (1)catheter 22 or (2) the sheath disposed within catheter 22, around stent50 so as to compress stent 50 within either (1) catheter 22 or (2) thesheath disposed within catheter 22. Torque-delivering and anchor-pullingtool 208 may then be rotated in order to unscrew anchor 40 from thetissue, and the entire system may be extracted from the body, orrepositioned in the heart, depending on the need of a given patient.

Reference is again made to FIGS. 7A-D. FIGS. 7C-D show the decouplingand release of torque-delivering and anchor-pulling tube 208 andmanipulator 206 from adapter 218 and anchor 40. This release occurstypically following the deployment of stent 50 (if provided), asdescribed hereinabove. As shown in FIG. 7A, system 200 comprises areleasable adapter holder 212 which is shaped so as to define arms 214which have a tendency to expand radially. Holder 212 surroundsmanipulator 206, as shown in FIG. 7C. During the delivery of anchor 40toward implantation site 30 and the subsequent rotation of anchor 40 toscrew anchor 40 into tissue at site 30, a distal end 204 of overtube 202is disposed adjacently to loop 216 such that a distal end portion ofovertube 202 surrounds and compresses arms 214 of holder 212 (as shownin FIG. 7B). Following the pulling of anchor 40 by torque-delivering andanchor-pulling tube 208, overtube 202 is retracted slightly in order toexpose arms 214 of holder 212. Responsively, arms 214 expand radially(FIG. 7C) and release adapter 218 (and thereby anchor 40) from holder212.

As shown in FIG. 7D, overtube 202 is held in place while the physicianretracts tube 208 so as to collapse and draw aims 214 into the distalend portion of overtube 202. Overtube 202 is then slid proximally withincatheter 22 leaving behind anchor 40, adapter 218 coupled to anchor 40,loop 216, longitudinal member 42, and stent 50 (if provided). Catheter22, that houses overtube 202 and the components disposed therein, isextracted from the body of the patient.

For some applications, such as those described hereinabove withreference to FIGS. 7A-D, longitudinal member 42 has a length of at least10 mm, no more than 40 mm, and/or between 10 and 40 mm.

Reference is again made to FIGS. 1A-D. It is to be noted thattissue-engaging elements 60 a and 60 b may be implanted at theirrespective implantation sites 30 and 50, as described hereinabove, byadvancing catheter 22 and tissue-engaging elements 60 a and 60 b throughsuperior vena cava 10, mutatis mutandis.

FIGS. 2A-B show a system 100 for repairing tricuspid valve 4 comprisingfirst and second stents 50 a and 50 b, first and second longitudinalmembers 42 a and 42 b, and first and second tissue anchors 40 a and 40b. First tissue anchor 40 a defines first tissue-engaging element 60 a.First stent 50 a defines second tissue-engaging element 60 b. Secondtissue anchor 40 b defines a third tissue-engaging element 60 c. Secondstent 50 b defines a fourth tissue-engaging element 60 d. For someapplications of the present invention, following the implantation offirst tissue-engaging element 60 a and second tissue-engaging element 60b, such as described hereinabove with reference to FIGS. 1A-D, third andfourth tissue-engaging elements 60 c and 60 d are then implanted. Asdescribed hereinabove, first implantation site 30, as shown, comprises aportion of tissue that is in a vicinity of the commissure betweenanterior leaflet 14 and posterior leaflet 16. First implantation site 30may comprise a portion of tissue that is between (1) the middle of thejunction between the annulus and anterior leaflet 14, and (2) the middleof the junction between the annulus and posterior leaflet 16.

Following the implantation of first and second tissue-engaging elements60 a and 60 b, catheter 22 is retracted from the body of the patient.Outside the body of the patient, catheter 22 is reloaded with third andfourth tissue-engaging elements 60 c and 60 d. Catheter 22 is thenreintroduced within the body of the patient and is advanced toward rightatrium 6, as shown in FIG. 2A, such that distal end 23 thereof passesthrough first stent 50 a and toward atrium 6. It is to be noted that aproximal end portion of longitudinal member 42 a is coupled to secondtissue-engaging element 60 b and is not disposed within catheter 22.

Subsequently, a second tissue anchor 40 b (i.e., an anchor that issimilar to tissue anchor 40 a, as described hereinabove) is implanted ata second portion of cardiac tissue at a third implantation site 32.Third implantation site 32 includes a portion of cardiac tissue in thevicinity of tricuspid valve 4 (e.g., a second portion of tissue of theannulus of tricuspid valve 4, as shown). Third implantation site 32, asshown, comprises a portion of tissue that is between (1) the middle ofthe junction between the annulus and anterior leaflet 14, and (2) themiddle of the junction between the annulus and posterior leaflet 16. Forsome applications, third implantation site 32 may comprise a secondportion of the wall that defines right atrium 6. For other applications,third implantation site 32 may comprise a portion of cardiac tissue inthe right ventricle, e.g., a portion of the wall that defines the rightventricle, a ventricular portion of the annulus of valve 4, or a portionof a papillary muscle of the right ventricle.

Following implantation of third tissue-engaging element 60 c, catheter22 is retracted and tension is applied to third tissue-engaging element60 c in a manner as described hereinabove with reference to FIGS. 1C-Dwith regard to the application of tension to implantation site 30.Additionally, tension is applied to a second longitudinal member 42 bwhich couples third and fourth tissue-engaging elements 60 c and 60 d,e.g., in a manner as described hereinabove with regard to the pulling offirst longitudinal member 42 a, with reference to FIG. 1C. As describedherein, a level of regurgitation of valve 4 may be monitored during thepulling tissue of third implantation site 32 toward second implantationsite 52 and of second longitudinal member 42 b.

Additionally, responsively to the pulling of tissue at first and thirdimplantation sites 30 and 32 toward second implantation site 52,anterior leaflet 14 is drawn toward septal leaflet 12, andbicuspidization is achieved. Also, responsively to the pulling, aportion of tissue that is between first and third implantation sites 30and 32 is cinched. Further, responsively to the pulling, posteriorleaflet 16 is reduced and moved out of a plane of valve 4 during thebicuspidization.

Reference is now made to FIG. 2B. Once the physician determines that theregurgitation of valve 4 is reduced or ceases, and valve 4 has beenrepaired, catheter 22 is decoupled from fourth tissue-engaging element60 d and/or from second longitudinal member 42 b, and the physicianretracts catheter 22 in order to expose fourth tissue-engaging element60 d, i.e., second stent 50 b, as shown. During the advancement ofcatheter 22 toward atrium 6, second stent 50 b is disposed within adistal portion of catheter 22 in a compressed state. Following initialretracting of catheter 22, second stent 50 b is exposed and is allowedto expand within a lumen of first stent 50 a, as shown, in order tocontact a wall of inferior vena cava 8. Responsively to the expanding,second stent 50 b is implanted in second implantation site 52 andmaintains the tension of second longitudinal member 42 b on secondtissue anchor 40 b and thereby on the portion of cardiac tissue to whichanchor 40 b is coupled.

It is to be noted that second stent 50 b is implanted within the lumenof first stent 50 a by way of illustration and not limitation, and thatfor some applications of the present invention, first and second stents50 a and 50 b may be implanted coaxially at second implantation site 52.

It is to be noted that third and fourth tissue-engaging elements 60 cand 60 d and second longitudinal member 42 b are typically fabricatedfrom the same material, e.g., nitinol, from a single piece. That is,third and fourth tissue-engaging elements 60 c and 60 d and secondlongitudinal member 42 b typically define a single continuous implantunit.

Reference is now made to FIGS. 3A-C, which are schematic illustrationsof a system 110 for repairing tricuspid valve 4, which comprises first,second, and third tissue-engaging elements 60 a, 60 b, and 60 c, andfirst and second longitudinal members 42 a and 42 b, in accordance withsome applications of the present invention. System 110 is similar tosystem 100 described hereinabove with reference to FIGS. 2A-B, with theexception that system 110 does not comprise second stent 50 b; rather,as shown in FIGS. 3B-C, a proximal end portion 112 of secondlongitudinal member 42 b is shaped so as to define one or more engagingelements 114 (e.g., hooks or barbs, as shown). Following the implantingof third tissue-engaging element 60 c and the subsequent pulling ofsecond longitudinal member 42 b, catheter 22 facilitates coupling ofengaging elements 114 with the struts of stent 50 (as shown in FIG. 3Cwhich is an enlarged image of stent 50 and the proximal portion ofsecond longitudinal member 42 b of FIG. 3B). The coupling of engagingelements 114 to stent 50 maintains the tension applied to longitudinalmember 42, and thereby maintains the tension on third tissue-engagingelement 60 c in order to maintain the remodeled state of tricuspid valve4.

It is to be noted that third tissue-engaging element 60 c, secondlongitudinal member 42 b, and engaging elements 114 and proximal endportion 112 of second longitudinal member 42 b are typically fabricatedfrom the same material, e.g., nitinol, from a single piece. That is,third tissue-engaging element 60 c, second longitudinal member 42 b, andengaging elements 114 and proximal end portion 112 of secondlongitudinal member 42 b typically define a single continuous implantunit.

Reference is now made to FIGS. 2A-B and 3A-C. For some applications,following the implantation the tissue-engaging elements at theirrespective implantation sites, as described hereinabove, a length ofeach one of first and second longitudinal members 42 a and 42 b isadjusted by an adjustable mechanism, as described hereinbelow withreference to FIGS. 5A-B. Adjusting mechanism 150 typically comprises amechanical element which shortens a length of each one of first andsecond longitudinal members 42 a and 42 b. For some applications, arespective adjustable mechanism 150 may be permanently coupled to eachone of first and second longitudinal members 42 a and 42 b (not shown);

each mechanism 150 comprises an adjusting element, e.g., a spool forlooping respective portions of longitudinal members 42 a and 42 btherearound, a crimping bead for crimping and shortening respectiveportions of longitudinal members 42 a and 42 b, a ratchet element, or adefaulting element which deforms respective portions of longitudinalmembers 42 a and 42 b. For other applications, the adjusting mechanismcomprises only an adjusting tool which may comprise an adjustingelement, e.g., a crimping bead for crimping and shortening respectiveportions of longitudinal members 42 a and 42 b, or a deforming elementwhich deforms respective portions of longitudinal members 42 a and 42 b.In either application, a level of regurgitation of valve 4 may bemonitored during the adjusting of the respective lengths of first andsecond longitudinal members 42 a and 42 b.

FIGS. 4A-C show a system 120 for repairing tricuspid valve 4 comprisingfirst and second stents 130 and 132 implanted in superior vena cava 10and inferior vena cava, respectively, in accordance with someapplications of the present invention. A catheter 122 is advancedthrough vasculature of the patient such that a distal end 124 ofcatheter 122 toward superior vena cava 10, as shown in FIG. 4A. Catheter122 is advanced from a suitable access location, e.g., catheter 122 maybe introduced into the femoral vein of the patient, through inferiorvena cava 8, and toward superior vena cava 10. During the advancement ofcatheter 122 toward superior vena cava 10 and inferior vena cava 8,stents 130 and 132 are disposed within a distal portion of catheter 122in a compressed state.

In FIG. 4B, first stent 130 is deployed from within catheter 122 andexpands to contact tissue of a wall of superior vena cava 10. Thisportion of the wall of the superior vena cava de fines firstimplantation site 30 in such applications of the present invention.Additionally, first stent member 130 defines first tissue-engagingelement 60 a in such applications of the present invention. It is to benoted that the portion of superior vena cava 10 in which stent 130 isimplanted defines a portion of tissue that is in the vicinity of valve4.

Catheter 122 is then retracted so as to pull and apply tension tolongitudinal member 42. Longitudinal member 42 is pulled directly bycatheter 122 and/or indirectly by pulling stent member 132 disposedwithin catheter 122. For some applications, during the pulling, a levelof regurgitation of tricuspid valve 4 may be monitored, becauseresponsively to the pulling, the geometry of the wall of atrium 6 isaltered and the leaflets of tricuspid valve 4 are drawn together so asto reduce and eliminate regurgitation of valve 4.

Once the physician determines that the regurgitation of valve 4 isreduced or ceases, and valve 4 has been repaired, the physiciandecouples catheter 122 from second stent member 132 disposed thereinand/or from longitudinal member 42, and then retracts catheter 122 inorder to expose second tissue-engaging element 60 b, i.e., second stentmember 132, as shown. Following initial retracting of catheter 122,second stent member 132 is exposed and is allowed to expand and contacta wall of inferior vena cava 8, as shown in FIG. 4C. Responsively to theexpanding, second stent member 132 is implanted in second implantationsite 52 and maintains the tension of longitudinal member 42 on firststent member 130 and thereby maintains the altered geometry of the wallof atrium 6 and of the leaflets of tricuspid valve 4.

Reference is again made to FIGS. 4A-C. For some applications, followingthe deploying of first and second tissue-engaging elements 60 a and 60 b(i.e., first and second stents 130 and 132, respectively), a distancebetween first and second tissue-engaging elements 60 a and 60 b isadjusted by an adjustable mechanism, as described hereinbelow withreference to FIGS. 5A-B. In such applications, a length of longitudinalmember 42 between first and second stents 130 and 132 may be adjusted byan adjusting mechanism 150, as shown in FIGS. 5A-B. Adjusting mechanism150 typically comprises a mechanical element which shortens a distanceof longitudinal member 42 between first and second stents 130 and 132.For some applications, adjustable mechanism 150 may be permanentlycoupled to longitudinal member 42 (not shown) and comprises an adjustingelement, e.g., a spool for looping portions of longitudinal member 42therearound, a crimping bead for crimping and shortening a portion oflongitudinal member 42, a ratchet element, or a deforming element whichdeforms a portion of longitudinal member 42 in order to shorten itslength between first and second stents 130 and 132. A level ofregurgitation and repair of valve 4 may be monitored during theadjusting of the distance between first and second tissue-engagingelements 60 a and 60 b by adjusting mechanism 150.

It is to be noted that first and second stents 130 and 132 andlongitudinal member 42 are typically fabricated from the same material,e.g., nitinol, from a single piece. That is, first and second stents 130and 132 and longitudinal member 42 typically define a single continuousimplant unit.

Reference is yet again made to FIGS. 4A-C. It is to be noted that distalend 124 of catheter 122 may first be advanced toward inferior vena cava,and not first toward superior vena cava, as shown in FIG. 4A. In such anembodiment, catheter 122 may be introduced into the external jugularvein, through the subclavian vein, through superior vena cava 10, andtoward inferior vena cava 8. Alternatively, catheter 122 may beintroduced into the basilic vein, through the subclavian vein, throughsuperior vena cava 10 and toward inferior vena cava 8. It is to be notedthat any suitable access location may be used to introduce catheter 122into the vasculature of the patient.

Reference is still made to FIGS. 4A-C. For some applications, one orboth of stents 130 and/or 132 comprise a plurality of interconnectedsuperelastic metallic struts, such as described hereinabove withreference to FIG. 1D.

Reference is now made to FIGS. 5A-B, which are schematic illustrationsof a system 140 for repairing tricuspid valve 4 comprising first andsecond tissue anchors 40 a and 40 b coupled together by longitudinalmember 42, in accordance with some applications of the presentinvention. In such applications, first tissue anchor 40 a defines firsttissue-engaging element 60 a, and second tissue anchor 40 b definessecond tissue-engaging element 60 b. Tissue anchors 40 a and 40 b maycomprise any suitable anchor for puncturing, squeezing, or otherwiseengaging cardiac tissue of the patient. As shown by way of illustrationand not limitation, tissue anchors 40 a and 40 b comprise helical tissueanchors which puncture and screw into the cardiac tissue. It is to benoted that first and second tissue-engaging elements 60 a and 60 b(i.e., first and second tissue anchors 40 a and 40 b) and longitudinalmember 42 are fabricated from the same material, e.g., nitinol, from asingle piece. That is, first and second tissue-engaging elements 60 aand 60 b and longitudinal member 42 define a single continuous implantunit.

A delivery catheter is advanced through vasculature of the patient, inmanner as described hereinabove with regard to catheter 22 withreference to FIG. 1A. The catheter is advanced toward first implantationsite 30 and facilitates implantation of first tissue anchor 40 a in thecardiac tissue. As shown, first implantation site 30 includes a firstportion of tissue of the annulus of valve 4 at the mural side of valve4, by way of illustration and not limitation. For some applications,first implantation site 30 may include a first portion of the wall ofatrium 6 of heart 2. As shown by way of illustration and not limitation,first implantation site 30 includes a portion of tissue of the annulusat the commissure between anterior leaflet 14 and posterior leaflet 16.It is to be noted that first implantation site 30 may be implanted atany suitable location along and in the vicinity of the annulus of valve4.

The delivery catheter is then advanced toward second implantation site52 and facilitates implantation of second tissue anchor 40 b in thecardiac tissue. For some applications, as the catheter is advancedtoward second implantation site, longitudinal member 42 is pulled todraw together the leaflets of valve 4, while a level of regurgitation ofvalve 4 is monitored. As shown, second implantation site 52 includes asecond portion of tissue of the annulus of valve 4 at the septal side ofvalve 4, by way of illustration and not limitation. For someapplications, second implantation site 52 may include a second portionof the wall of atrium 6 of heart 2. As shown by way of illustration andnot limitation, second implantation site 52 includes a portion of tissueof the annulus inferior of the middle of septal leaflet 12. It is to benoted that first implantation site 30 may be implanted at any suitablelocation along and in the vicinity of the annulus of valve 4, e.g., atthe commissure between posterior leaflet 16 and septal leaflet 12.

For such an application, by applying tension to longitudinal member 42,anterior leaflet 14 and septal leaflet 12 are drawn together, andbicuspidization of valve 4 is achieved. For some applications, duringthe adjusting of mechanism 150, a retrievable stent may be deployed ininferior vena cava 8 so as to stabilize system 140 during the adjustingof adjusting mechanism 150. It is to be further noted thattissue-engaging elements 60 a and 60 b and the delivery catheter may beadvanced toward atrium 6 through superior vena cava, mutatis mutandis.

For some applications of the present invention, system 140 comprises oneor more anchor-manipulating tools (not shown for clarity ofillustration), that is slidably disposed within the delivery catheter.The anchor-manipulating tool is slid distally with in the catheter so asto push distally tissue anchors 40 a and 40 b and expose tissue anchors40 a and 40 h from within the catheter. For some applications of thepresent invention, the anchor-manipulating tool(s) is(/are) reversiblycouplable to anchors 40 a and 40 b, and facilitate(s) implantation ofanchors 40 a and 40 b in the cardiac tissue. For applications in whichanchors 40 a and 40 b comprises respective helical tissue anchor, asshown, the operating physician rotates the anchor-manipulating tool(s)from a site outside the body of the patient in order to rotate anchors40 a and 40 b, and thereby screw at least respective distal portions ofanchors 40 a and 40 b in the cardiac tissue.

Reference is again made to FIGS. 5A-B. It is to be noted that first andsecond implantation sites 30 and 52 include cardiac tissue that isupstream of valve 4 by way of illustration and not limitation, and thateither or both first and second implantation sites may include cardiactissue that is downstream of valve 4.

Typically, following implantation of first and second tissue anchors 40a and 40 b, a length of longitudinal member 42, that is disposed betweenfirst and second tissue anchors 40 a and 40 b, is adjusted by adjustingmechanism 150. Adjusting mechanism 150 typically comprises a mechanicalelement which shortens a distance of longitudinal member 42 betweenfirst and second tissue-engaging elements 60 a and 60 b. For someapplications, adjustable mechanism 150 may be permanently coupled tolongitudinal member 42 (as shown in FIG. 5B) and comprises an adjustingelement, e.g., a spool for looping portions of longitudinal member 42therearound, a crimping bead for crimping and shortening a portion oflongitudinal member 42, a ratchet element, or a deforming element whichdeforms a portion of longitudinal member 42 in order to shorten itslength between first and second tissue-engaging elements 60 a and 60 b.

For other applications, system 140 comprises only an adjusting tool(which functions as an adjusting mechanism) and not adjusting mechanism150. In such applications, the adjusting tool may comprise an adjustingelement, e.g., a crimping bead for crimping and shortening a portion oflongitudinal member 42, or a deforming element which deforms a portionof longitudinal member 42 in order to shorten its length between firstand second tissue-engaging elements 60 a and 60 b.

In either application, a level of regurgitation of valve 4 may bemonitored during the adjusting of the distance between first and secondtissue-engaging elements 60 a and 60 b by adjusting mechanism 150.

Following the adjusting of the distance between first and secondimplantation sites 30 and 52, the adjusting tool and the deliverycatheter are decoupled from longitudinal member 42 and are extractedfrom the body of the patient.

Reference is now made to FIG. 5B, which is a schematic illustration ofanother configuration of system 140, in accordance with someapplications of the present invention. This configuration of system 140is generally similar to the configuration described above with referenceto FIG. 5A, except that the system comprises a third tissue-engagingelement 60 c (i.e., a third tissue anchor), in addition to first andsecond tissue-engaging elements 60 a and 60 b. Third tissue-engagingelement 60 c is implanted at third implantation site 32, such as usingthe techniques described hereinabove with reference to FIG. 5A. For someapplications, third implantation site 32 may include a third portion ofthe wall of atrium 6. By way of illustration and not limitation, thethree implantation sites may include portions of tissue of the annulusof the three leaflets of the valve, such as at the middle of theleaflets.

Tissue-engaging elements 60 a, 60 b, and 60 c are coupled tolongitudinal members 42 a, 42 b, and 42 c, respectively. Thelongitudinal members are coupled together by adjusting mechanism 150.For some applications, adjusting mechanism 150 comprises a spool forlooping portions of the longitudinal members therearound, and a ratchetelement which allows the spool to rotate in only one direction. Rotationof the spool loops the longitudinal member therearound, therebyshortening the effective lengths of the members and applying tensionthereto, to draw the leaflets toward one another, such as describedhereinabove with reference to FIG. 5A. As a result, a geometry of thewall of the right atrium may be altered.

Reference is now made to FIG. 6 which is a schematic illustration of asystem 700 for repairing tricuspid valve 4 comprising firsttissue-engaging element 60 a implanted at a portion of the annuls ofvalve 4 and a third tissue-engaging element 60 c implanted at a portionof a papillary muscle 72 in the right ventricle of the patient, inaccordance with some applications of the present invention. It is to benoted that third implantation site 32 comprises papillary muscle 72 byway of illustration and not limitation, and that third implantation site32 may comprise any potion of a wall of the right ventricle (e.g., aportion of tissue of the annulus at the ventricular surface of valve 4,a portion of the wall of the ventricle in the vicinity of valve 4, aportion of tissue in the vicinity of the apex of heart 2, or any othersuitable portion of the wall of the ventricle).

Reference is now made to FIGS. 2A-B and 6. First, second, and thirdtissue-engaging elements 60 a-c of FIG. 6 are implanted in cardiactissue in a manner as described hereinabove with reference to FIGS.2A-B, with the exception that, in order to implant third tissue-engagingelement 60 c, catheter 22 passes through the leaflets of valve 4 intothe right ventricle and implants third tissue-engaging element 60 c intissue of the ventricle. Following coupled of third tissue-engagingelement 60 c in FIG. 6, second stent 50 b is deployed in secondimplantation site 52 in inferior vena cava 8, as described hereinabovewith reference to FIG. 2B.

Reference is now made to FIGS. 3A-C and 6. It is to be noted, that forsome applications, second longitudinal member 42 b is coupled at aproximal end thereof to one or more barbs 114 (i.e., and is notconnected to second stent 50, as shown). Barbs 114 enable secondlongitudinal member 42 b to be coupled to stent 50 that is in connectionwith first longitudinal member 42 a, and thereby maintain tension onthird implantation site 32 and maintain coaptation of at least anteriorleaflet 14 and septal leaflet 12.

Reference is again made to FIG. 6. Such an application of at least onetissue-engaging element 60 in a portion of tissue of the ventricle ofheart 2, in some applications, facilitates independent adjustment ofvalve 4 and a portion of the ventricle wall of heart 2. That is, forsome application, geometric adjustment of the right ventricle to improveits function is achieved.

For some applications, following the deploying of first, second, third,and fourth tissue-engaging elements 60 a-d (i.e., first and secondanchors 40 a and 40 b, and first and second stents 50 a and 50 b), (1) adistance between first and second tissue-engaging elements 60 a and 60 bis adjustable by first adjustable mechanism, and (2) a distance betweenthird and fourth tissue-engaging elements 60 c and 60 d is adjustable bya second adjustable mechanism, as described hereinbelow with referenceto FIG. 5A. In such applications, (1) a length of first longitudinalmember 42 a between first and second tissue-engaging elements 60 a and60 b may be adjusted by a first adjusting mechanism 150, as shown inFIG. 5A, and (2) a length of second longitudinal member 42 b betweenthird and fourth tissue-engaging elements 60 c and 60 d may be adjustedby a second adjusting mechanism 150, as shown in FIG. 5A or 5B.

Adjusting mechanisms 150 typically each comprise a mechanical elementwhich shortens a distance of respective longitudinal members 42 a and 42b. For some applications, adjustable mechanisms 150 may be permanentlycoupled to respective longitudinal members 42 a and 42 b (not shown) andeach comprise an adjusting element, e.g., a spool for looping portionsof longitudinal members 42 a and 42 b therearound, a crimping bead forcrimping and shortening respective portions of longitudinal members 42 aand 42 b, a ratchet element, or a deforming element which deformsrespective portions of longitudinal members 42 a and 42 b in order toshorten its length between the respective tissue-engaging elements 60.For other applications, system 700 comprises an adjusting mechanismscomprising only an adjusting tool (not shown). In such applications, theadjusting tool may comprise an adjusting element, e.g., a crimping beadfor crimping and shortening respective portions of longitudinal members42 a and 42 b, or a deforming element which deforms respective portionsof longitudinal members 42 a and 42 b. In either application, a level ofregurgitation of valve 4 may be monitored and the adjustment of thegeometry of the right ventricle is monitored during (1) the adjusting ofthe distance between first and second implantation sites 30 and 52, and(2) the adjusting of the distance between third and second implantationsites 32 and 52, respectively.

Reference is now made to FIGS. 8 and 9, which are schematicillustrations of a system 800 for repairing tricuspid valve 4, inaccordance with respective applications of the present invention. Asshown in FIGS. 8 and 9, system 800 comprises first, second, third, andfourth tissue-engaging elements 60 a, 60 b, 60 c, and 60 d. System 800is similar in some respects to system 110 described hereinabove withreference to FIGS. 3A-B, with the exception that system 800 typicallycomprises only exactly one longitudinal member 42. Typically,longitudinal member 42 is directly coupled to first tissue-engagingelement 60 a, and indirectly coupled to tissue-engaging elements 60 cand 60 d by a longitudinal sub-member 802. Typically, one end oflongitudinal sub-member 802 is coupled to tissue-engaging element 60 c,and the other end of the sub-member is coupled to tissue-engagingelement 60 d. For some applications, as shown, longitudinal member 42 isnot fixed to longitudinal sub-member 802; instead, longitudinalsub-member 802 engages, e.g., is hooked on or looped over, longitudinalmember 42, at a junction 804 during deployment of the longitudinalsub-member. Alternatively, a ring is provided that couples thelongitudinal sub-member to the longitudinal member (configuration notshown).

For some applications, as shown in FIG. 8, a superior vena cava approachis used to implant system 800, in which tissue-engaging elements 60 a,60 c, and 60 d are advanced into atrium 6 via superior vena cava 10, andtissue-engaging element 60 b is deployed in the superior vena cava. FIG.9 illustrates an inferior vena cava approach, in which tissue-engagingelements 60 a, 60 c, and 60 d are advanced into atrium 6 via inferiorvena cava 8, and tissue-engaging element 60 b is deployed in theinferior vena cava. Typically, one of tissue-engaging elements 60 a, 60c, and 60 d is deployed at the septal side of tricuspid valve 4 in thecaudal part of the base of the septal leaflet, and the other two oftissue-engaging elements 60 a, 60 c, and 60 d are deployed at the muralside of the valve, dividing the entire mural side in three equal spaces,generally at the middle of anterior leaflet and the commissure betweenthe anterior and posterior leaflets. For some applications, yet anothertissue-engaging element is deployed at the mural side of the valve(configuration not shown).

An anchor-deployment tube is deployed into atrium 6, for example, usingtechniques described hereinabove with reference to FIG. 1A. Firsttissue-engaging element 60 a is deployed at first implantation site 30,such as using anchoring techniques described herein. First implantationsite 30 includes a portion of cardiac tissue in the vicinity oftricuspid valve 4 (e.g., a first portion of tissue of the annulus oftricuspid valve 4, as shown). For example, in the approach shown in FIG.8, first implantation site 30 may be on the mural side of the annulus ofthe valve (e.g., at anterior leaflet 14), approximately centered betweentwo of the commissures of the valve. In the approach shown in FIG. 9,first implantation site 30 may be on the mural side of the annulus(e.g., at posterior leaflet 16), approximately centered between two ofthe commissures of the valve. Alternatively, although typically lessdesirable, first implantation site 30 may be approximately at acommissure of the valve.

During the implantation using system 800, the distal end of theanchor-deployment tube is advanced to third implantation site 32. Thirdtissue-engaging element 60 c is deployed at third implantation site 32,such as using anchoring techniques described herein. Third implantationsite 32 includes a portion of cardiac tissue in the vicinity oftricuspid valve 4 (e.g., a second portion of tissue of the annulus oftricuspid valve 4, as shown). For example, in the approach shown in FIG.8, third implantation site 32 may be on the mural side of the annulus ofthe valve (e.g., at posterior leaflet 16), approximately centeredbetween two of the commissures of the valve. In the approach shown inFIG. 9, third implantation site 32 may be on the mural side of theannulus of the valve (e.g., at anterior leaflet 14), approximatelycentered between two of the commissures of the valve.

Alternatively, although typically less desirable, third implantationsite 32 may be approximately at a commissure of the valve.

Subsequently to implantation at third implantation site, the distal endof the anchor-deployment tube is advanced to a fourth implantation site34. As mentioned above, longitudinal sub-member 802 extends betweentissue-engaging elements 60 c and 60 d. As fourth tissue-engagingelement 60 d is brought to fourth implantation site 34, longitudinalsub-member 802 engages, e.g., becomes hooked on or looped over,longitudinal member 42 at junction 804. Fourth tissue-engaging element60 d is deployed at fourth implantation site 34, such as using anchoringtechniques described herein. Fourth implantation site 34 includes aportion of cardiac tissue in the vicinity of tricuspid valve 4 (e.g., asecond portion of tissue of the annulus of tricuspid valve 4, as shown).For example, in the approaches shown in FIGS. 8 and 9, fourthimplantation site 34 may be on septal side of the annulus of the valve(e.g., at the caudal part of the base of septal leaflet 12,approximately centered between two of the commissures of the valve.Alternatively, although typically less desirable, fourth implantationsite 34 may be approximately at a commissure of the valve.

Following implantation at fourth implantation site 34, theanchor-deployment tube is withdrawn into the vena cava. Secondtissue-engaging element 60 b (stent 50) pulls on longitudinal member 42,which directly pulls on first tissue-engaging element 60 a, andindirectly pulls on tissue-engaging elements 60 c and 60 d vialongitudinal sub-member 802. Responsively, a distance between theleaflets of tricuspid valve 4 is adjusted to reduce and eliminateregurgitation through valve 4, and thereby, valve 4 is repaired. Forsome applications, during the pulling of longitudinal member 42, a levelof regurgitation of tricuspid valve 4 is monitored. Longitudinal member42 is pulled until the regurgitation is reduced or ceases. Once thephysician determines that the regurgitation of valve 4 is reduced orceases, and valve 4 has been repaired, second tissue-engaging element 60b (e.g., stent 50) is deployed from the anchor-deployment tube in thevena cava, such as described hereinabove, thereby implanting thetissue-engaging element at second implantation site 52, as shown inFIGS. 8 and 9.

For some applications, stent 50 comprises a plurality of interconnectedsuperelastic metallic struts, such as described hereinabove withreference to FIG. 1D.

For some applications, following the implantation the tissue-engagingelements at their respective implantation sites, as describedhereinabove, a length of longitudinal member 42 is adjusted by anadjustable mechanism, as described hereinabove with reference to FIG. 5Aor 5B. Adjusting mechanism 150 typically comprises a mechanical elementwhich shortens a length of longitudinal member 42. For someapplications, adjustable mechanism 150 may be permanently coupled tolongitudinal member 42; mechanism 150 comprises an adjusting element,e.g., a spool for looping a portion of longitudinal member 42therearound, a crimping bead for crimping and shortening the portion oflongitudinal member 42, a ratchet element, or a deforming element whichdeforms the portion of longitudinal member 42. For other applications,system 800 comprises an adjusting mechanism comprising only an adjustingtool. In such applications, the adjusting tool may comprise an adjustingelement, e.g., a crimping bead for crimping and shortening the portionof longitudinal member 42, or a deforming element which deforms theportion of longitudinal member 42. In either application, a level ofregurgitation of valve 4 may be monitored during the adjusting of thelength of longitudinal member 42.

Reference is now made to FIGS. 10A-D, which are schematic illustrationsof tissue anchors 40, in accordance with respective applications of thepresent invention. One or more of these anchors may be used as anchors40 in the applications described hereinabove with reference to FIGS.1A-D, 2A-B, 3A-C, 5A-B, 6, 8, 9, 11A-C, 12A-C, 13C, and/or 14C.

In the configuration shown in FIG. 10A, anchor 40 comprises a distaltissue-piercing tip 972 fixed to a plurality of arms 974, which extendfrom tip 972 in respective generally distal and radially-outwarddirections. The arms are inserted entirely into the tissue, therebyhelping to couple the anchor to the tissue. For some applications, agreatest width W1 of anchor 40 is at least 6.5 mm, no more than 39 mm,and/or between 6.5 and 39 mm, such as 13 mm. For some applications, alength L2 of anchor 40, measured along an axis of the anchor from tipsof arms 974 to the end of tip 972 of the anchor, is at least 5 mm, nomore than 30 mm, and/or between 5 and 30 mm, such as 10 mm. For someapplications, a greatest diameter D1 of tip 972 is at least 1 mm, nomore than 6 mm, and/or between 1 and 6 mm, such as 2 mm.

In the configurations shown in FIGS. 10B and 10C, anchor 40 isconfigured to radially contract and expand in a manner generally similarto that of an umbrella (but without the umbrella cloth). The anchor isinserted into the tissue in a radially-contracted (closed) state and istransitioned to a radially-expanded (open) state, either automaticallyor by the surgeon, in order to fix the anchor within the tissue. Forsome applications, such as shown in FIG. 10B, the anchor is configuredto assume the radially-expanded state when resting; the anchor is heldin a radially-contracted state during deployment, and transitions to theradially-expanded state upon being released. For other applications,such as shown in FIG. 10C, the anchor is configured to assume theradially-contracted state when resting; the anchor is deployed in theradially-contracted state, and is actively transitioned to theradially-expanded state by the surgeon after being inserted into thetissue.

Anchor 40 comprises distal tissue-piercing tip 972, which is fixed at adistal end of a post 976 (which typically comprises a tube). The anchorfurther comprises a plurality of ribs 978 (e.g., three or four). Ribs978 are coupled to the anchor near distal tip 972, such that the ribscan articulate with post 796, thereby changing respective angles betweenthe ribs and the post. The anchor further comprises a runner 980 (whichtypically comprises a tube), which is slidably coupled to post 976, suchthat the runner can slide along the post. A plurality of stretchers 982are coupled to runner 980 and respective ones of the ribs, such thatstretchers can articulate with the runner and the respective ribs. Eachof the stretchers may comprise one or more elongated elements; by way ofexample, each of the stretchers is shown comprising two elongatedelements. Typically, tips 984 of ribs 978 (i.e., at the ends not coupledto the anchor) are blunt.

For some applications, such as the configuration shown in FIG. 10B, theanchor at least partially comprises a shape-memory alloy (e.g.,nitinol), and the anchor's natural, resting state is theradially-expanded (open) state. The anchor is crimped inside a catheterso that it remains radially-contracted (closed) until deployed. Oncedeployed into the tissue, the catheter is pulled back and the anchor isallowed to open (i.e., automatically transition to the radially-expandedstate).

For some applications, in order to allow retraction of the anchor (suchas if the anchor has been improperly positioned, or needs to be removedfor another reason), the proximal end of runner 980 (i.e., the endfarther from tip 972) is removably coupled to an inner tube positionedwithin the catheter. For example, an outer surface of the proximal endof runner 980 and an inner surface of the inner tube near a distal endthereof may be threaded, to enable the removable coupling. Runner 980thus remains coupled to the inner tube until released, such as byrotating the inner tube with respect to the runner (the tissue preventsthe runner from also rotating). In order to retract the anchor, post 976is pushed in a distal direction while the runner is still coupled to theinner tube, thereby moving post 976 with respect to runner 980 andtransitioning the anchor back to its radially-contracted (closed) state.The anchor can thus be withdrawn into the catheter, repositioned, anddeployed again at a different location. The surgeon rotates the innertube to decouple the anchor once the location of the anchor has beenfinalized.

For some applications, in the configuration shown in FIG. 10C, anchor 40further comprises a tube positioned around post 976, proximal to runner980 (i.e., farther from tip 972). The tube is used to push runner 980 ina distal direction (toward the tip), in order to open the umbrella.

For some applications, a greatest width W2 of anchor 40, when radiallyexpanded, is at least 6.5 mm, no more than 39 mm, and/or between 6.5 and39 mm, such as 13 mm. For some applications, a length L3 of anchor 40,measured along an axis of the anchor from tips 984 of ribs 978 to theend of tip 972 of the anchor when the anchor is radially expanded, is atleast 5 mm, no more than 30 mm, and/or between 5 and 30 mm, such as 10mm. For some applications, a greatest diameter D2 of tip 972 is at least0.4 mm, no more than 2.4 mm, and/or between 0.4 and 2.4 mm, such as 0.8mm. For some applications, a greatest diameter D3 of post 976 is atleast 0.3 mm, no more than 1.8 mm, and/or between 0.3 and 1.8 mm, suchas 0.6 mm. For some applications, each of ribs 978 has a length of atleast 6 mm, no more than 20 mm, and/or between 6 and 20 mm, such as 10mm.

In the configuration shown in FIG. 10D, anchor 40 is barbed. Forexample, the anchor may be generally flat, and is shaped so as to defineone or more barbs 990, which typically extend from both sides of theanchor. The barbs help couple the anchor to the tissue. For someapplications, a greatest width W3 of anchor 40, excluding barbs 990, isat least 0.85 mm, no more than 5.1 mm, and/or between 0.85 and 5.1 mm,such as 1.7 mm. For some applications, a greatest width W4 of anchor 40,including barbs 990, is at least 1.25 mm, no more than 7.5 mm, and/orbetween 1.25 and 7.5 mm, such as 2.5 mm. For some applications, a lengthL4 of anchor 40, measured along an axis of the anchor from a distal endof the barbed portion to the proximal tip of the anchor, is at least 5mm, no more than 30 mm, and/or between 5 and 30 mm, such as 9.5 mm. Forsome applications, a greatest thickness T of anchor 40 is at least 0.1mm, no more than 0.6 mm, and/or between 0.1 and 0.6 mm, such as 0.2 mm.

Reference is now made to FIGS. 11A-C, which are schematic illustrationsof a delivery tool system 1000 for implanting anchor 40, in accordancewith some applications of the present invention. Delivery tool system1000 may be used, for example, to rotate, locate, place, and implant ananchor in combination with the applications described herein withreference to FIGS. 1A-D, 2A-B, 3A-C, 5A-B, 6, 8, 9, 13A-C, 14A-C, 15A-B,16A-B, and 17. Although longitudinal member 42 is shown in FIGS. 11A-Cas being fixed to stent 50, this is not necessarily the case, and toolsystem 200 thus may also be used in combination with the applicationsthat do not utilize stent 50, such as those described herein withreference to FIGS. 3C and 5A-B.

FIG. 11A shows an exploded view of some of the components of deliverytool system 1000 and its spatial orientation relative to stent 50,longitudinal member 42, and anchor 40. In such an application,longitudinal member 42 comprises a plurality of fibers aligned so as toform a band 1140. Band 1140 is coupled at a first portion 1141 thereof(e.g., a proximal portion, as shown) to a portion of stent 50. Stent 50comprises a plurality of mechanical structural elements 1651 arranged soas to form a tubular structure of stent 50 in a radially-expanded stateof stent 50. First portion 1141 of band 1140 is coupled to the portionof stent 50 via a tension-distributing element 1160, as will bedescribed hereinbelow with reference to FIGS. 13A-C, 14A-C, and 15A-B.

A second portion 1143 of band 1140 is coupled to tissue anchor 40 via aconnecting element 1240 that is coupled to a proximal portion of anchor40 via an adapter head 1230. Tissue anchor 40 comprises a helical tissueanchor having a central lumen about a longitudinal axis 1155. Connectingelement 1240 is shaped so as to define aflexible-longitudinal-member-coupler 1242 at a proximal portion ofconnecting element 1240. Flexible-longitudinal-member-coupler 1242 isshaped so as to define an opening 1244 configured for coupling of secondportion 1143 of band 1140 to connecting element 1240. Typically secondportion 1143 of band 1140 is coupled to connecting element 1240 bythreading it through opening 1244 and forming a distal loop 1142.

Connecting element 1240 is shaped so as to provide an annular loop 1246at a portion of element 1240 that is distal to opening 1244 andflexible-longitudinal-member-coupler 1242. Annular loop 1246 has aninner diameter that is larger than an outer diameter of the anchor 40.Annular loop 1246 surrounds the proximal-most coil in a manner whichfacilitates rotation of anchor 40 about axis 1155 freely by facilitatingrotation of the proximal-most loop of anchor 40 freely about axis 1155.For some applications loop 1246 rotates around the proximal portion ofanchor 40.

Adapter head 1230 is shaped so as to define a distal tissue-anchorcoupling element 1233 which has an outer diameter that is equal to orless than a diameter of the lumen of anchor 40 in a manner in whichtissue-anchor coupling element 1233 fits within the lumen of anchor 40and is welded to a proximal portion of anchor 40 in order to coupleadapter head 1230 to anchor 40 (as shown hereinbelow with reference toFIGS. 12A-C). Adapter head 1230 is shaped so as to define an annularelement 1234 which has an outer diameter that is larger than a diameterof an opening provided by annular loop 1246. Thus, adapter head 1230prevents decoupling of connecting element 1240 from anchor 40 sinceconnecting element 1240 is not welded to anchor 40.

System 1000 comprises a torque-delivering tool comprising atorque-delivering cable 1204 that is slidably disposed within a lumen ofa tube 1202. Torque-delivering cable 1204 is welded at a distal endthereof to a first coupling 1220 shaped so as to define a male couplingelement 1222. Adapter head 1230 is shaped so as to provide a secondcoupling 1232 shaped so as to define a female coupling elementconfigured to fit the male coupling element 1222. When coupled together,as will be described hereinbelow with reference to FIGS. 12A-C, firstand second couplings 1220 and 1232, respectively, coupletorque-delivering cable 1204 to tissue anchor 40. Torque-deliveringcable 1204 is rotated in order to rotate first coupling 1220 and secondcoupling 1232 of anchor head 1230, and thereby tissue anchor 40.

Since adapter head 1230, having second coupling 1232, is welded to aproximal portion of anchor 40, when adapter head 1230 is rotated, anchor40 is rotated. As anchor 40 is rotated, the proximal-most coil of anchor40 rotates freely within annular loop 1246, and anchor 40 rotates withrespect to annular loop 1246.

As shown, the proximal portion of connecting element 1240 comprisingflexible-longitudinal-member-coupler 1242, shaped so as to defineopening 1244, is generally crescent-shaped. A portion of tube 1202 in avicinity of distal end 1205 of tube 1202 is coupled to ananti-entanglement device 1224 which is shaped so as to define a distalelement 1226 that is generally crescent-shaped. Distal element 1226 isdisposed alongside the proximal portion of connecting element 1240 in amanner in which the crescent shaped are aligned, as shown in FIG. 11B.In such a configuration, during rotation of torque-delivering cable 1204to rotate anchor 40, tube 1202 is not rotated around cable 1204, but isheld in place, which (1) keeps anti-entanglement device 1224 maintainedin a relative position with reference to connecting element 1240, andthereby (2) connecting element 1240 is not rotated as anchor 40 isrotated, and flexible member 42 (or band 1140, in this application) isnot rotated when anchor is rotated. In such a manner, as anchor 40rotates with respect to annular loop 1246, anchor 40 rotates withrespect to flexible member 42, thus anti-entanglement device 1224prevents band 1140 from entangling during rotation of anchor 40.

As shown in FIG. 11B, tissue anchor 40 defines first tissue-engagingelement 60 a, and stent 50 defines second tissue-engaging element 60 b.

Reference is now made to FIG. 11C which shows a tool 1002 forfacilitating implanting of tissue anchor 40 and expansion of stent 50within the blood vessel of the patient. Tool 1002 comprises a proximalhandle portion 1004 which is coupled to a proximal portion of a firstshaft 1016. As shown in the enlarged cross-sectional image on themiddle-right of FIG. 11C, stent 50 crimped within a sheath 1190. Aproximal portion of stent 50 is shaped so as to define two or moredelivery-tool couplers 1159. A distal end of first shaft 1016 is shapedso as to provide one or more stent-couplers 1017. A respective deliverytool coupler 1159 is coupled to shaft 1016 by being coupled to arespective stent coupler 1017. When sheath 1190 surrounds stent 50,stent 50 is maintained in a crimped state and couplers 1159 remaincoupled to couplers 1017. As shown, tube 1202 and torque-deliveringcable 1204 pass through a lumen of stent 50 in its crimped, orradially-compressed state.

As described hereinabove, tissue anchor 40 defines first tissue-engagingelement 60 a and stent 50 defines second tissue-engaging element 60 b.As described hereinabove, tissue anchor 40 is implanted in tissue of thepatient prior to positioning stent 50 in the blood vessel of thepatient. That is, tissue anchor 40 is exposed from within sheath 1190and implanted in tissue of the patient while stent 50 remains crimpedwithin sheath 1190. Since torque-delivering cable 1204 and tube 1202pass through the lumen of stent 50, during rotation of anchor 40, anchor40 rotates with respect to stent 50 while stent remains static.

Tool 1002 comprises a “Y”-shaped connector 1014 coupled to a proximalend of shaft 1016. A first arm of connector 1014 provides a lumen forpassage of a guidewire tube 1013 that is configured to hold a guidewire(not shown). A second arm of connector 1014 provides a lumen for passageof tube 1202 that surrounds torque-delivering cable 1204. As shown inthe cross-sectional image on the top-right, tube 1202 surrounding cable1204 passes alongside guidewire tube 1013. Guidewire tube 1013 extendsthrough tool 1002 and through a lumen provided by a distal atraumatictip 1192. For such an application, tip comprises a symmetrical tip 1196.Tip 1192 enables atraumatic advancement the shafts of tool 1002 throughvasculature of the patient. Tip 1192 comprises a flexible biocompatiblematerial, e.g., polyurethane, and a radiopacity-enhancing material suchas an embedded marker made from a radiopaque substance such as Pt—Ir, oralternatively by adding BaSO4 to the biocompatible material.

Reference is now made to FIGS. 18A-B, which are schematic illustrationsof atraumatic tip 1192 comprising an asymmetrical atraumatic tip 2000having an asymmetrical body 1198, in accordance with some applicationsof the present invention. As shown, tip 2000 is shaped so as to providea lumen for passage therethrough of guidewire tube 1013. Tip 2000 isshaped so as to define a recess 2002 for housing anchor 40 during theadvancement of the shafts of tool 1002 through the vasculature of thepatient. Anchor 40, flexible-longitudinal-member-coupler 1242, band1140, and guidewire tube 1013 are shown in phantom to indicate theirpositioning relative to tip 2000. Once the physician wishes to releaseanchor 40 from within recess 2002, the physician pushes on guidewiretube 1013 so as to disengage tip 2000 from distal end 1191 of sheath1190 (shown in FIG. 11C) and distance tip 2000 and anchor 40 from distalend 1191. The physician then pulls proximally on cable 1204 so as toretract anchor 40 from within recess 2002. Once anchor 40 is exposedfrom within recess 2002, anchor 40 may be rotated, as describedhereinabove with reference to FIGS. 11C and 12A, and may be disengagedfrom first coupling 1220, as described hereinabove with reference toFIGS. 11C and 12B-C.

Reference is again made to FIG. 11C. The shafts of tool 1002 are guidedalong the guidewire (not shown for clarity of illustration) to therespective implantation sites of anchor 40 and stent 50. During theadvancement of the shafts through the vasculature, tip 1192 is coupledto a distal end 1191 of sheath 1190 (e.g., by having a proximal portionof tip 1192 disposed within a lumen of sheath 1190 at distal end 1191thereof. Prior to deployment and implantation of anchor 40 from withinsheath 1190, tip 1192 is pushed distally so as to decouple tip 1192 fromdistal end 1191 of sheath 1190. Tip 1192, for some applicationscomprises symmetrical tip 1196. Symmetrical tip 1196 facilitatesrecoupling of tip 1192 to distal end 1191 of sheath 1190 following thedecoupling of tip 1192 from sheath 1190.

Reference is now made to FIGS. 12A-C, which are schematic illustrationsof first and second couplings 1220 and 1232, respectively, in theirlocked state (FIG. 12A) and their unlocked state (FIG. 12C), inaccordance with some applications of the present invention. As describedhereinabove, first coupling 1220 matingly engages second coupling 1232when a distal end 1205 of tube 1202 surrounding torque-delivering cable1204 is disposed distally. When distal end 1205 is disposed distally, asshown in FIG. 12A, a distal portion of tub 1202 surrounds first andsecond couplings 1220 and 1232, respectively, in a manner which keepsfirst and second couplings 1220 and 1232, respectively, coupledtogether. As shown in FIG. 12A, and as described hereinabove, the distalportion of tube 1202 is coupled to anti-entanglement device 1224. Asshown in the cross-sectional images of FIGS. 12A-C, distal element 1226of anti-entanglement device 1224 is disposed behindflexible-longitudinal-member-coupler 1242 at the proximal portion ofconnecting element 1240.

Reference is now made to FIGS. 11C and 12A. As shown in FIG. 11C, tool1002 comprises a steering mechanism 1018 that surrounds shaft 1016 andis coupled to a proximal end 1193 of sheath 1190. Steering mechanism1018 facilitates proximal and distal movement of a steering wire (notshown for clarity) with respect to mechanism 1018, tube 1202 andguidewire tube 1013. Steering mechanism 1018 comprises a user-engagingelement 1195 which enables the physician to facilitate steering ofsheath 1190. Steering mechanism 1018 comprises an actuating mechanism1194 comprising a plurality of teeth which facilitate proximal anddistal movement of the steering wire when user-engaging element 1195 isactuated by the physician using system 1000.

When the physician wishes to expose anchor 40 from within sheath 1190,the physician slides the cable 1204 and tube 1202 together so as toexpose anchor 40. For some applications, cable 1204 and tube 1202 areslid when the physician pushes at least handle portion 1004 so as topush tube 1202 (and cable 1204 disposed therein) distally in order topush anchor 40 distally within sheath 1190 and expose anchor 40 fromwithin sheath 1190. During the sliding, mechanism 1018 is held in placeso as to prevent distal sliding of sheath 1190 during the distal slidingof anchor 40. (When the physician desires to deploy stent 50, thephysician slides sheath 1190 proximally by sliding mechanism 1018 withrespect to shaft 1016 so as to expose stent 50. For such applications,stent 50 is exposed from within sheath 1190 and is allowed to expandradially and disengage delivery-tool couplers 1159 of stent 50 fromstent-couplers 1017 of tool 1002).

When the physician wishes to position anchor 40 into the correctanatomical place such as the anteroposterior commissure, the physicianactuates user-engaging element 1195 to actuate steering mechanism 1018which pulls the steering cable, causing steering of sheath 1190 in orderto deflect sheath 1018 in one direction. The physician may then rotatethe handle portion of mechanism 1018 to change the deflection directionand reach the correct anatomical positioning of anchor 40.

As shown in FIG. 11C, proximal handle portion 1004 comprises ananchor-deployment actuator 1006 and a holder 1008. Actuator 1006, asshown in the cross-sectional image, is coupled to torque-deliveringcable 1204 such that when first and second couplings 1220 and 1232,respectively, are coupled together (as shown in FIG. 12A), rotation ofactuator 1006 rotates torque-delivering cable 1204 in order to rotateanchor 40. Typically, anchor 40 is rotated once anchor 40 is exposedfrom within sheath 1190, as described hereinabove, in order to screwanchor 40 into tissue of the patient.

Holder 1008 is coupled to a proximal portion of tube 1202 that surroundscable 1204. Holder 1008 is shaped so as to define a proximal recess1009, with transverse holes 1011. Actuator 1006 is shaped so as todefine a distal protrusion 1007 which is shaped so as to fit withinrecess 1009 of holder 1008.

As shown in FIGS. 11C and 12A, the distal portion of tube 1202 disposedaround first and second couplings 1220 and 1232, respectively. In such aconfiguration, protrusion 1007 of actuator 1006 is disposed proximallyto holder 1008. Furthermore, holder 1008 comprises a safety 1010 (e.g.,a suture which extends transverse to the longitudinal lumen of recess1009 through holes 1011) which prevents protrusion 1007 from slidingwithin recess 1009 of holder 1008.

When the physician desires to disengage first and second couplings 1220and 1232, respectively, the physician releases safety 1010 (e.g., bycutting the suture) and pushes actuator 1006 distally so that protrusion1007 of actuator 1006 slides within recess 1009 of holder 1008. Duringthe pushing of actuator 1006, the physician holds holder 1008.Responsively, since actuator 1006 is coupled to cable 1204, cable 1204is slid distally (in the direction as indicated by arrow 2) so thatfirst and second couplings 1220 and 1232, respectively, are exposed fromwithin the distal portion of tube 1202. Additionally, since tissueanchor 40 is implanted in tissue of the patient, the tissue exerts aforce on tube 1202 which pushes tube 1202 proximally, in the directionas indicated by arrow 1. Consequently, first and second couplings 1220and 1232, respectively, are exposed from within the distal portion oftube 1202, as shown in FIG. 12B.

As shown in FIG. 12C, the physician tilts tube 1202 (e.g., clockwise, asshown) in order to disengage male coupling element 1222 of firstcoupling 1220 from the female coupling element of second coupling 1232.Thereby, tool 1002 is disengaged from anchor 40. Following thedisengaging of tool 1002 from anchor 40, anchor 40, adapter head 1230,and connecting element 1240 remain implanted at the implantation site.

Following the implantation of tissue anchor 40 at first implantationsite 30, sheath 1190 is retracted proximally by pulling proximallymechanism 1018 so as to expose band 1140 coupled to tissue anchor 40.Sheath 1190 is navigated by mechanism 1194 such that distal end 1191 ofsheath 1190 is positioned in second implantation site 52. As tool 1002is navigated, tension is applied to band 1140 in order to draw togetherfirst and second implantation sites 30 and 52, respectively, and repairvalve 4, in a manner as described hereinabove with reference to FIGS.1A-D.

For some applications, during the pulling of band 1140 by tool 1002, alevel of regurgitation of tricuspid valve 4 is monitored and a parameterindicative of repair of valve 4 is monitored. For example, leafletanatomy during the opening and closing of valve 4 is assessed using animaging device such as intracardiac echocardiography, transthoracicechocardiography or transesophageal echocardiography. For someapplications, during the monitoring, measurements used to assess theefficiency of the procedure are evaluated pre-, during, andpost-procedure. For example, these measurements could include, but notexclusively, measuring the echocardiographic distance between theanteroposterior commissure and the rim at the junction of the inferiorvena cava and the right atrium, or measuring the echocardiographicregurgitant volume through tricuspid valve 4. Band 1140 is pulled untilthe regurgitation is reduced or ceases.

Once the physician determines that the regurgitation of valve 4 isreduced or ceases, and valve 4 has been repaired, sheath 1190 isretracted proximally as described hereinabove with reference to FIG. 11Cby pulling proximally on sheath 1190, which is done by pullingproximally on mechanism 1018, so as to expose stent 50 from withinsheath 1190. As stent 50 expands radially, delivery-tool couplers 1159of stent 50 expand away and disengage from stent-couplers 1017 of tool1002, thereby disengaging stent 50 from tool 1002. Following thedisengaging of tool 1002 from stent 50, tool 1002 is extracted from thebody of the patient.

Reference is now made to FIGS. 13A-C, which are schematic illustrationsof a stent 1150 comprising a proximal portion 1156 and a distal portion1157, each of portions 1156 and 1157 comprising a plurality ofmechanical structural elements 1651 shaped so as to define a pluralityof peaks 1152, a plurality of valleys 1154, and a plurality ofinterconnectors 1158, in accordance with some applications of thepresent invention. FIG. 13A shows stent 1150 in an assembled state, andFIG. 13B shows stent 1150 in a flattened state in which stent 1150 iscut longitudinally and flattened, for clarity of illustration. It is tobe noted, however, that the configuration shown in FIG. 13A defines theconfiguration of stent 1150 in a radially-expanded state.

The structural configuration of stent 1150 provided by mechanicalstructural elements 1651 may be formed by expanding a laser-slottedmetallic tube, or may be chemically etched from a flat sheet and weldedto a tube, or may be formed from a single wire, or may be formed byassembling individual wire elements, or by any other method ofconstruction known to those skilled in the art. The design of stent 1150can be laser cut from a small diameter tube, expanded to the finaldiameter, or may be cut from a large diameter tube, which is equal tothe final diameter of a fully expanded stent or which may be furtherexpanded to an even larger diameter.

Stent 1150 is shaped so as to provide a plurality of coaxially-disposedannular ring portions 1151. Each ring portion 1151 is shaped so as todefine a plurality of peaks 1152 and a plurality of valleys 1154. Asshown, each of the plurality of interconnectors 1158 is orientedvertically. As shown in exemplary ring portions 1151 a and 1151 b, thering portions are aligned in a manner in which peaks 1152 and 1154 arein phase. Thus, interconnectors 1158 are vertically disposed betweenrespective valleys 1154 of respective ring portions 1151.

Such a configuration of mechanical structural elements 1651 providesstent 1150 with a property of generally maintaining its longitudinallength L5 measured along longitudinal axis 1155, during radial expansionof stent 1150 from a radially-compressed state of stent 1150.Additionally, such a configuration of mechanical structural elements1651 in distal portion 1157 of stent 1150 facilitates partialcompressibility retrievability/retractability into sheath 1190 (asdescribed hereinabove with reference to FIG. 11C) of distal portion 1157following radial expansion of distal portion 1157. That is, sheath 1190is slidable proximally to expose distal portion 1157 from within thesheath and allow distal portion 1157 to radially expand while proximalportion 1156 remains disposed radially-compressed within sheath 1190.Since (1) peaks 1152 of distal portion 1157 all point distally, and (2)interconnectors 1158 connect valleys 1154 of distal portion 1157, thereis no portion of distal portion 1157 which protrudes from the tubularstructure of stent 1150, which would otherwise interfere with distalsliding of sheath 1190 to compress and retrieve/retract distal portion1157 within sheath 1190. Therefore, distal portion 1157 isretrievable/retractable within sheath 1190. As such stent 1150 isretrievable up to ½ deployment, as shown.

Each annular ring portion 1151 comprises a plurality of struts 1153.Each strut has a width W7 of between 50 and 1000 micron, e.g., between100 and 500 micron, for example, 200 micron. Each interconnector 1158has a width W6 of between 50 and 500 micron e.g., 200 micron.

Stent 1150 is shaped so as to provide a plurality of delivery-toolcouplers 1159 at a proximal end 1300 thereof, as described hereinabovewith reference to FIG. 11C. Couplers 1159 are shaped so as to surroundand engage a plurality of tabs provided on shaft 1016 of tool 1002.

As shown in FIG. 13C, stent 1150 is coupled to flexible band 1140 at afirst portion thereof. i.e., a proximal portion thereof. Flexible band1140, in turn, is coupled at a second portion (i.e., a distal portionthereof) to tissue anchor 40. As described hereinabove with reference toFIGS. 1A-D, tissue anchor 40 is implanted in tissue of tricuspid valve4, then stent 50 is pulled in order to apply tension to flexible member42 in order to adjust the relative positioning of the leaflets of valve4, and then stent 50 is deployed in the blood vessel. Following thedeploying of stent 50 in the blood vessel, flexible member 42 exertstension force on stent 50. In order to distribute tension along thelength of stent 1150, stent 1150 is shaped so as to define atension-distributing element 1160.

Tension-distributing element 1160 has a width W5 of between 1 and 4 mm,e.g., 2.6 mm. Tension-distributing element 1160 has a longitudinallength L6 measured along longitudinal axis 1155 that is generally equalto longitudinal length L5 of stent 1150, as shown by way of illustrationand not limitation. Thus, tension-distributing element 1160, as shown inFIGS. 13A-C, comprises an elongate tension-distributing element 1161.That is, each one of lengths L5 and L6 of stent 1150 andtension-distributing element 1160, respectively, is between 20 and 120mm, e.g., 70 mm. It is to be noted that lengths L5 and L6 are shown asbeing generally equal by way of illustration and not limitation, andthat length L6 tension-distributing element 1160 may be smaller than thelongitudinal length of the stent, as shown hereinbelow with reference toFIGS. 15A-B, for example. That is, the longitudinal length oftension-distributing element 1160 is at least 15% of longitudinal lengthL5 of stent 1150.

Typically, a width of a widest mechanical structural element 1651 isbetween 100 and 500 micron, and width W5 of tension-distributing element1160 is between 1 and 4 mm. For some applications, width W5 oftension-distributing element 1160 is at least 13 times the width of thewidest mechanical structural element 1651.

Tension-distributing element 1160 is shaped so as to provide a pluralityof eyelets 1170 (FIGS. 13A-B). As shown in FIG. 13C, the proximalportion of flexible member 42 (or band 1140, as shown) is threadedthrough eyelets 1170 of tension-distributing element 1160. By threadingthe proximal portion of band 1140 through tension-distributing element1160, tension applied from anchor 40 and band 1140 is distributed alongthe length of stent 1150.

It is to be noted that tension-distributing element 1160 and mechanicalstructural elements 1651 are typically fabricated from a single piece oftubular alloy, typically superelastic, e.g., nitinol. For someapplications tension-distributing element 1160 and mechanical structuralelements 1651 are modularly assembled.

As shown in FIG. 13C, tissue anchor 40 defines first tissue-engagingelement 60 a, and stent 1150 defines second tissue-engaging element 60b.

Reference is now made to FIGS. 14A-C, which are schematic illustrationsof a stent 1400 comprising one or more (e.g., two, as shown) firstportions 1402 and one or more (e.g., one, as shown) second portion 1404,each of portions 1402 and 1404 comprising a plurality of mechanicalstructural elements 1651, in accordance with some applications of thepresent invention. FIG. 14A shows stent 1400 in an assembled state, andFIG. 14B shows stent 1400 in a flattened state in which stent 1400 iscut longitudinally and flattened, for clarity of illustration. It is tobe noted, however, that the configuration shown in FIG. 14A defines theconfiguration of stent 1400 in a radially-expanded state.

The structural configuration of stent 1400 provided by mechanicalstructural elements 1651 may be formed by expanding a laser-slottedmetallic tube, or may be chemically etched from a flat sheet and weldedto a tube, or may be formed from a single wire, or may be formed byassembling individual wire elements, or by any other method ofconstruction known to those skilled in the art. The design of stent 1400can be laser cut from a small diameter tube, expanded to the finaldiameter, or may be cut from a large diameter tube, which is equal tothe final diameter of a fully expanded stent or which may be furtherexpanded to an even larger diameter.

Portions 1402 of stent 1400 are each shaped so as to provide a plurality(e.g., two, as shown) of coaxially-disposed annular ring portions 1151.Each ring portion 1151 is shaped so as to define a plurality of peaks1152 and a plurality of valleys 1154. Stent 1400 comprises a pluralityof interconnectors 1158 (e.g., vertical interconnectors, as shown). Asshown in exemplary ring portions 1151 a and 1151 b, the ring portionsare aligned in a manner in which peaks 1152 and 1154 are in phase. Thus,interconnectors 1158 are vertically disposed between respective valleys1154 of respective ring portions 1151.

Portions 1402 have interconnectors 1158 a having a length of between 4and 25 mm, e.g., 9 mm. Portion 1404 is shaped so as to provide aplurality of elongate interconnectors 1158 b which connect portions1402. Interconnectors 1158 b have a length of between 20 and 80 mm,e.g., 50 mm. Taken together, peaks 1152, valleys 1154, andinterconnectors 1158 a of portions 1402 impart a greater radial force onsurrounding tissue in a radially-expanded state of stent 1400 thanportion 1404 of stent 1400, because portion 1404 comprises only elongateinterconnectors 1158 b. Such a configuration of stent 1400 provides anendoluminal implant which has a portion that exerts less radial force onsurrounding tissues; thus, stent 1400 is configured to be placed in ablood vessel (e.g., the inferior vena cava) that is surrounded byorgans. For applications in which stent 1400 is placed within the bloodvessel that is surrounded by organs, portion 1404 of stent 1400 exertsless radial force on the surrounding organs than portions 1402.

Such a configuration of mechanical structural elements 1651 providesstent 1400 with a property of generally maintaining its longitudinallength L5 measured along longitudinal axis 1155, during radial expansionof stent 1400 from a radially-compressed state of stent 1400.

Each annular ring portion 1151 comprises a plurality of struts 1153.Each strut has a width W7 of between 50 and 1000 micron, e.g., between100 and 500 micron, for example, 200 micron. Each interconnector 1158has a width W6 of between 50 and 500 micron e.g., 200 micron.

Stent 1400 is shaped so as to provide a plurality of delivery-toolcouplers 1159 at a proximal end 1300 thereof, as described hereinabovewith reference to FIG. 11C. Couplers 1159 are shaped so as to surroundand engage a plurality of tabs provided on shaft 1016 of tool 1002.

As shown in FIG. 14C, stent 1400 is coupled to flexible band 1140 at afirst portion thereof, i.e., a proximal portion thereof. Flexible band1140, in turn, is coupled at a second portion (i.e., a distal portionthereof) to tissue anchor 40. As described hereinabove with reference toFIGS. 1A-D, tissue anchor 40 is implanted in tissue of tricuspid valve 4(e.g., in the anteroposterior commissure), then stent 50 is pulled inorder to apply tension to flexible member 42 (or band 1140) in order toadjust the relative positioning of the leaflets of valve 4, and thenstent 50 is deployed in the blood vessel. Following the deploying ofstent 50 in the blood vessel, flexible member 42 exerts tension force onstent 50. In order to distribute tension along the length of stent 1400,stent 1400 is shaped so as to define tension-distributing element 1160.

As shown in FIG. 141B, tension-distributing element 1160 comprises amodular tension-distributing element having a distaltension-distributing element 1162 a and a proximal tension-distributingelement 1162 b. Distal tension-distributing element 1162 a and proximaltension-distributing element 1162 b are coupled together by aninterconnector 1158 b. Distal tension-distributing element 1162 a andproximal tension-distributing element 1162 b, together withinterconnector 1158, assume length L6 of tension-distributing element1160 that is generally equal to longitudinal length L5 of stent 1400, asshown by way of illustration and not limitation. Each one of lengths L5and L6, respectively, is between 20 and 120 mm, e.g., 70 mm. It is to benoted that lengths L5 and L6 are shown as being generally equal by wayof illustration and not limitation, and that length L6tension-distributing element 1160 may be smaller than the longitudinallength of the stent, as shown hereinbelow with reference to FIGS. 15A-B,for example. That is, the longitudinal length of tension-distributingelement 1160 is at least 15% of longitudinal length L5 of stent 1400.

Each one of distal tension-distributing element 1162 a and proximaltension-distributing element 1162 b has a longitudinal length L7 ofbetween 5 and 25 mm.

As shown in FIG. 14C, first portion 1143 of band 1140 is coupled todistal tension-distributing element 1162 a by being threaded througheyelet 1170 of element 1162 a. It is to be noted, however, that portion1143 of band 1140 may be coupled to both distal tension-distributingelement 1162 a and proximal tension-distributing element 1162 b byextending along the longitudinal length of stent 1400. It is to be notedthat longer the portion of band 1140 coupled along the longitudinallength of stent 1400, the more force is distributed along thelongitudinal length of stent 1400.

It is to be noted that tension-distributing elements 1162 a and 1162 band mechanical structural elements 1651 are fabricated from a singlepiece of tubular alloy, typically superelastic, e.g., nitinol. For someapplications tension-distributing elements 1162 a and 1162 b andmechanical structural elements 1651 are modularly assembled.

As shown in FIG. 14C, tissue anchor 40 defines first tissue-engagingelement 60 a, and stent 1400 defines second tissue-engaging element 60b.

Reference is now made to FIGS. 15A-B, which are schematic illustrationsof a stent 1500 comprising a first portions 1502, a second portion 1504,and a third portion 1506, each of portions 1502, 1504, and 1506comprising a plurality of mechanical structural elements 1651, inaccordance with some applications of the present invention. FIG. 15Ashows stent 1500 in an assembled state, and FIG. 15B shows stent 1500 ina flattened state in which stent 1500 is cut longitudinally andflattened, for clarity of illustration. It is to be noted, however, thatthe configuration shown in FIG. 15A defines the configuration of stent1500 in a radially-expanded state.

The structural configuration of stent 1500 provided by mechanicalstructural elements 1651 may be formed by expanding a laser-slottedmetallic tube, or may be chemically etched from a flat sheet and weldedto a tube, or may be formed from a single wire, or may be formed byassembling individual wire elements, or by any other method ofconstruction known to those skilled in the art. The design of stent 1500can be laser cut from a small diameter tube, expanded to the finaldiameter, or may be cut from a large diameter tube, which is equal tothe final diameter of a fully expanded stent or which may be furtherexpanded to an even larger diameter.

Portion 1504 comprises a plurality of struts 1520 each having a width W9of between 25 and 250 micron, e.g., 100 micron. Struts 1520 arespatially arranged so as to form a plurality of quadrilateral-shapedopenings 1522. e.g., diamond-shaped openings.

Portion 1506 comprises a plurality of struts 1530 each having a widthW10 of between 50 and 500 micron, e.g., 200 micron. Struts 1530 arespatially arranged so as to form a plurality of peaks 1152 and valleys1154.

Struts 1520 of portion 1504 are longer and thinner than struts 1530 ofportion 1506. Thus, portion 1506 exerts a greater radial force onsurrounding tissue in a radially-expanded state of stent 1500 thanportion 1504 of stent 1500. Additionally, the relative spatialarrangement of struts 1530 of portion 1506 (as compared with therelative spatial arrangement of struts 1520 of portion 1504) enablesportion 1506 to exert a greater radial force on surrounding tissue thanportion 1504.

Portion 1502 of stent 1500 is shaped so as to provide a plurality (e.g.,two, as shown) of coaxially-disposed annular ring portions 1151. Eachring portion 1151 is shaped so as to define a plurality of peaks 1152and a plurality of valleys 1154. Stent 1400 comprises a plurality ofinterconnectors 1158 (e.g., vertical interconnectors, as shown). Asshown in exemplary ring portions 1151 a and 1151 b, the ring portionsare aligned in a manner in which peaks 1152 and 1154 are in phase. Thus,interconnectors 1158 are vertically disposed between respective valleys1154 of respective ring portions 1151.

Each one of interconnectors 1158 of portion 1502 has a length of between4 and 25 mm, e.g., 9 mm. Taken together, peaks 1152, valleys 1154, andinterconnectors 1158 of portions 1502 impart a greater radial force onsurrounding tissue in a radially-expanded state of stent 1500 thanportions 1504 and 1506 of stent 1500. Such a configuration of stent 1500provides an endoluminal implant which has one or more portions (e.g.,portions 1504 and 1506) that exert less radial force on surroundingtissues than portion 1502; thus, stent 1500 is configured to be placedin a blood vessel (e.g., the inferior vena cava) that is surrounded byorgans. For applications in which stent 1500 is placed within the bloodvessel that is surrounded by organs, portion 1504 of stent 1500 exertsless radial force on the surrounding organs than portion 1502.

Such a configuration of mechanical structural elements 1651 providesstent 1500 with a property of generally maintaining its longitudinallength L5 measured along longitudinal axis 1155, during radial expansionof stent 1500 from a radially-compressed state of stent 1500.

Each annular ring portion 1151 comprises a plurality of struts 1153.Each strut has a width W7 of between 50 and 1000 micron, e.g., between100 and 500 micron, for example, 200 micron. Each interconnector 1158has a width W6 of between 50 and 500 micron e.g., 200 micron.

Stent 1500 is shaped so as to provide a plurality of delivery-toolcouplers 1159 at a proximal end 1300 thereof, as described hereinabovewith reference to FIG. 11C. Couplers 1159 are shaped so as to surroundand engage a plurality of tabs provided on shaft 1016 of tool 1002.

Stent 1500 is couplable to flexible band 1140 in a manner as describedhereinabove with reference to FIGS. 13A-C and 14A-C. Flexible band 1140,in turn, is coupled at a second portion (i.e., a distal portion thereof)to tissue anchor 40. As described hereinabove with reference to FIGS.1A-D, tissue anchor 40 is implanted in tissue of tricuspid valve 4(e.g., in the anteroposterior commissure), then stent 50 is pulled inorder to apply tension to flexible member 42 (e.g., band 1140) in orderto adjust the relative positioning of the leaflets of valve 4, and thenstent 50 is deployed in the blood vessel. Following the deploying ofstent 50 in the blood vessel, flexible member 42 exerts tension force onstent 50. In order to distribute tension along the length of stent 1500,stent 1500 is shaped so as to define tension-distributing element 1160.

As shown in FIG. 15B, tension-distributing element 1160 comprises adistal tension-distributing element 1163. Distal tension-distributingelement 1163 has a longitudinal length L11 of between 10 and 60 mm. Thatis, the longitudinal length of tension-distributing element 1160 is atleast 15% of longitudinal length L5 of stent 1500.

A first portion of band 1140 is coupled to distal tension-distributingelement 1163 is configured to be threaded through eyelet 1170 of element1163.

It is to be noted that tension-distributing element 1163 and mechanicalstructural elements 1651 may be fabricated from a single piece oftubular alloy, typically superelastic, e.g., nitinol. For someapplications tension-distributing element 1163 and mechanical structuralelements 1651 are modularly assembled.

Stent 1500 defines second tissue-engaging element 60 b.

The structural configuration of stent 1500 provided by mechanicalstructural elements 1651 may be formed by expanding a laser-slottedmetallic tube, or may be chemically etched from a flat sheet and weldedto a tube, or may be formed from a single wire, or may be formed byassembling individual wire elements, or by any other method ofconstruction known to those skilled in the art. The design of stent 1500can be laser cut from a small diameter tube, expanded to the finaldiameter, or may be cut from a large diameter tube, which is equal tothe final diameter of a fully expanded stent or which may be furtherexpanded to an even larger diameter.

Reference is now made to FIGS. 16A-B, which are schematic illustrationsof a stent system 1600 comprising a first stent 50 a and a second stent50 b shaped so as to be concentrically disposed within a lumen of stent50 a and facilitate anchoring of stent 50 a in the blood vessel, inaccordance with some applications of the present invention. Stent 50 a,as shown in FIGS. 16A-B comprises stent 1400 as described hereinabovewith reference to FIGS. 14A-C. It is to be noted, however, that stent 50a may comprise any one of the stents shown in FIGS. 1D, 13A-C, 14A-C,and 15A-B. It is to be noted that stents 50 a and 50 b define respectiveradially-expandable percutaneous, e.g., endoluminal, implants.

Stent 50 a comprises a plurality of mechanical structural elements 1651that are arranged so as to form a first tubular structure having a lumen1652 in a radially-expanded state of stent 50 a that has an innerdiameter D5 of between 18 and 45 mm, e.g., 24 mm, 28 mm, or 32 mm.

Stent 50 b comprises a radially-expandable implant 1610 that comprises aplurality of mechanical structural elements 1651 that are arranged so asto form a second tubular structure. Implant 1610 is shaped so as toprovide a plurality of tissue-engaging structures 1612 which protrudefrom the generally-tubular structure of implant 1610. For example,structures 1612 comprise barbs. Implant 1610 has an outer diameter D4 ina radially-expanded state of implant 1610, excluding tissue-engagingelements 1612, of between 18 and 45 mm, e.g., 24 mm, 28 mm, or 32 mm.Diameter D4 enables implant 1610 to expand at least as large as theinner diameter D5 of lumen 1652 of stent 50 b. When implant 1610 expandsto assume its expanded state within lumen 1652, as shown in FIG. 16B,tissue-engaging structures 1612 extend between mechanical structuralelements 1651 of stent 50 a in order to engage and be anchored to tissueof the blood vessel. Since elements 1612 extend between mechanicalstructural elements 1651 of stent 50 a, stent 50 b of implant 1610facilitates anchoring of stent 50 a in the blood vessel.

Tissue anchor 40 defines first tissue-engaging element 60 a, stent 50 adefines second tissue-engaging element 60 b, and stent 50 b definesthird tissue-engaging element 60 c.

As described hereinabove, tissue anchor 40 is implanted in firstimplantation site 30, and then stent 50 b is deployed in the bloodvessel. Following the deploying of stent 50 b in the blood vessel,implant 1610 is position and deployed within lumen 1652 of stent 50 a.

As described hereinabove, following implantation of stent 50 a in theblood vessel, tension is applied to stent 50 a by flexible member 42(e.g., band 1140), which may cause migration of stent 50 a within theblood vessel. By deploying stent 50 b within lumen 1652 of stent 50 a,tissue-engaging structures 1612 expand between mechanical structuralelements 1651 of stent 50 a in order to engage tissue of the bloodvessel and anchor stent 50 a to the blood vessel. Additionally, theexpanding of stent 50 b within lumen 1652 of stent 50 a providesadditional radial force of stent 50 b in its expanded state againststent 50 b, in order to apply additional radial force of stent 50 aagainst the blood vessel.

The structural configuration of implant 1610 provided by mechanicalstructural elements 1651 may be formed by expanding a laser-slottedmetallic tube, or may be chemically etched from a flat sheet and weldedto a tube, or may be formed from a single wire, or may be formed byassembling individual wire elements, or by any other method ofconstruction known to those skilled in the art. The design of implant1610 can be laser cut from a small diameter tube, expanded to the finaldiameter, or may be cut from a large diameter tube, which is equal tothe final diameter of a fully expanded stent or which may be furtherexpanded to an even larger diameter. It is to be noted that mechanicalstructural elements 1651 may be arranged in a relative spatialorientation that is different from the orientation shown in FIG. 16A.

FIG. 17 shows a system 1700 for implanting second tissue-engagingelement 60 b in a blood vessel other than inferior vena cava 8 andsuperior vena cava 10, e.g., left hepatic vein 11, as shown, inaccordance with some applications of the present invention. It is to benoted that second tissue-engaging element 60 b comprises stent 1400 asdescribed hereinabove with reference to FIGS. 14A-C, by way ofillustration and not limitation. It is to be noted that secondtissue-engaging element 60 b may comprise any one of the stents orendoluminal implants shown in FIGS. 1D, 13A-C, 14A-C, 15A-B, and 16A-B.First and second tissue-engaging elements 60 a and 60 b are implanted atfirst and second implantation sites 30 and 52, in a manner as describedhereinabove with reference to FIGS. 1A-D, 7A-D, 11A-C, and 12A-C. It isto be noted that for applications in which second tissue-engagingelement 60 b is implanted in the hepatic vein, element 60 b in anexpanded state thereof has an outer diameter of between 8.5 and 12 mm,and has a length of between 17 and 36 mm.

For some applications, flexible member 42 comprises band 1140, asdescribed hereinabove.

For applications in which second implantation site 52 includes lefthepatic vein 11, flexible member 42 has a length of between 150 and 300mm, e.g., 200 mm.

It is to be noted that although implantation site 52 includes a portionof left hepatic vein 11, implantation site 52 may be a portion of aright hepatic vein or a middle hepatic vein.

Reference is made to FIGS. 1A-D. For applications in which secondimplantation site 52 includes inferior vena cava 8 or superior vena cava10, flexible member 42 has a length of between 20 and 80 mm, e.g.,between 40 and 60 mm.

It is to be noted that the scope of the present invention includesimplanting second tissue-engaging element 60 b in a coronary sinus ofthe patient. For such an application, flexible member has a length ofbetween 10 and 40 mm, e.g., 20 mm.

Reference is now made to FIGS. 13A-C, 14A-C, 15A-B, and 16A-B. It is tobe noted that any suitable configuration of tension-distributing element1160 shown in any of FIGS. 13A-C, 14A-C, 15A-B, and 16A-B may be part ofany of stents 1150, 1400, or 1500 shown in FIGS. 13A-C, 14A-C, 15A-B,and 16A-B.

FIG. 19 shows a system 2500 comprising an endoluminal percutaneousimplant 2504 comprising two or more radially-expandable rings 2502 a and2502 b which define second tissue-engaging element 60 b, in accordancewith some applications of the present invention. Rings 2502 a and 2502 bare shown as being elliptical by way of illustration and not limitation,and that rings 2502 a and 2502 b may be circular. Implant 2504 iscoupled to a portion of longitudinal member 42 at a junction betweenrings 2502 a and 2502 b, by way of illustration and not limitation.

First and second elements 60 a and 60 b are implanted in manner asdescribed hereinabove with reference to FIGS. 1A-D, 7A-D, 11A-C, and12A-C. During the advancement of implant 2504, implant 2504 is crimpedand radially-compressed within a sheath. For example, implant 2504 maybe advanced within sheath 1190, as described hereinabove with referenceto FIGS. 11A-C and 12A-C.

Implant 2504 exerts a strong radial force on tissue of the blood vesselwhile defining a low profile volume of mechanical structural elements.

It is to be noted that although second implantation site 52 includes aportion of inferior vena cava 8, second implantation site may include aportion of superior vena cava 10, hepatic vein 11, or any other suitableblood vessel.

Reference is now made to FIGS. 20-26, which are schematic illustrationsof a system 2600 comprising a first tissue-engaging element 60 a coupledto a first flexible longitudinal member 2612 and a secondtissue-engaging element 60 b coupled to a second flexible longitudinalmember 2660, for repairing a tricuspid valve 4 of a heart 2 of apatient, in accordance with some applications of the present invention.First tissue-engaging element 60 a comprises a tissue anchor 40 which isdesignated for implantation at least in part in cardiac tissue at afirst implantation site 30. It is to be noted that tissue anchor 40comprises a helical tissue anchor by way of illustration and notlimitation and that tissue anchor 40 may comprise any tissue anchor forpuncturing or clamping cardiac tissue, including, but not limited to,the tissue anchors described hereinabove with reference to FIGS. 7A-D,10A-D 11A-C, 12A-C, 13A-C, and 14A-C. Second tissue-engaging element 60b comprises a percutaneous implant, for example, an endoluminal implant,e.g., stent 50, which is designated for implantation in a portion of ablood vessel, e.g., inferior vena cava 8 (such as shown in FIG. 26) orsuperior vena cava 10 (not shown), at second implantation site 52.Except as described hereinbelow, system 2600 is similar to system 20described hereinabove with reference to FIGS. 1A-D. System 2600comprises one or more longitudinal members 42, which couple togetherfirst and second tissue-engaging elements 60 a and 60 b, as describedhereinabove. For such applications, system 2600 comprises (1) firstlongitudinal member 2612 (which defines a first of the one or morelongitudinal members 42) coupled at a first portion thereof to firsttissue-engaging element 60 a, and (2) second longitudinal member 2660(which defines a second of the one or more longitudinal members 42)coupled at a first portion thereof to second tissue-engaging element 60b.

Typically, longitudinal members 2612 and 2660 comprise a flexiblebiocompatible textile e.g. polyester, nylon, PTFE, ePTFE, PEEK, PEBAX™,and/or superelastic material, e.g., nitinol. Typically, longitudinalmembers 2612 and 2660 comprise a plurality of fibers which are aligned,e.g., woven or intertwined, to form a fabric band, as is describedhereinabove with reference to FIGS. 11A-C, 13C, and 14C. In someapplications of the present invention, longitudinal members 2612 and2660 each comprise a braided polyester suture (e.g., DACRON™). In otherapplications of the present invention, longitudinal members 2612 and1660 are coated with polytetrafluoroethylene (PTFE). In someapplications of the present invention, longitudinal members 2612 and2660 each comprise a plurality of wires that are intertwined to form arope structure. For some applications, at least a part of each oflongitudinal members 2612 and 2660 comprises a tension spring and/or aplurality of coils.

FIG. 20 shows a first-tissue-engaging-element delivery tool 2602 beingadvanced toward first implantation site 30 at tricuspid valve 4 throughsuperior vena cava 10 from a suitable point of entry, in a directionfrom B to A. Additionally, a snare 2606 shaped to define a loop 2608 isadvanced by a snare delivery tool 2604 toward first implantation site 30at tricuspid valve 4 through inferior vena cava 8 from a suitable pointof entry, in a direction from A to B. It is to be noted that system 2600can be advanced in opposite direction to the one as shown in FIGS.20-26. That is, first-tissue-engaging-element tool 2602 may be advancedthrough inferior vena cava 8 in the direction from A to B, while snaredelivery tool 2604 may be advanced through superior vena cava 10 in thedirection from B to A.

FIGS. 21 and 22A-D show a delivery system to implant firsttissue-engaging element 60 a in tissue of the annulus of valve 4. Tissueanchor 60 a is described hereinabove with reference to FIGS. 1A-D and11A-C. A distal end portion 2613 of first longitudinal member 2612 islooped around flexible-longitudinal-member-coupler 1242, and within aportion of opening 1244 of connecting element 1240. As describedhereinabove with reference to FIG. 11A, adapter head 1230 is coupled toa proximal portion of anchor 40 via annular loop 1246. As anchor 40 isrotated, the proximal-most coil of anchor 40 rotates freely withinannular loop 1246, and anchor 40 rotates with respect to annular loop1246.

Anchor 40 is rotated by the torque-delivering tool comprisingtorque-delivering cable 1204. As described hereinabove,torque-delivering cable 1204 is welded at a distal end thereof to firstcoupling 1220, which defines a first coupling element. As shown in FIG.22D, has a first-coupling-element longitudinal axis along axis 2611.First coupling 1220 is shaped so as to define a first-coupling-elementmain body portion 2620 shaped so as to define afirst-coupling-element-main-body passage 2621. First coupling 1220 isshaped so as to define a first-coupling-element secondary body portion2622 coaxial with main body portion 2620. First-coupling elementsecondary body portion 2622 is shaped so as to define afirst-coupling-element-secondary-body-portion passage 2623 that iscoaxial with first-coupling-element-main-body passage 2621. Firstcoupling 1220 is shaped so as to define a connecting element 2624 thatconnects first-coupling-element secondary body portion 2622 tofirst-coupling-element main body portion 2620. First coupling 1220 isshaped so as to define a first-coupling-element space 2625 between mainbody portion 2620 and secondary body portion 2622.

As shown in FIG. 22D, adapter head 1230 defines a second couplingelement having a longitudinal axis along axis 2611 (FIGS. 22C-D). Head1230 is shaped so as to define a second-coupling-element main bodyportion 2630 shaped so as to define a second-coupling-element-main-bodypassage 2631. Head 1230 is shaped so as to define asecond-coupling-element secondary body portion 2632 coaxial with mainbody portion 2630. The second-coupling element secondary body portion2632 is shaped so as to define asecond-coupling-element-secondary-body-portion passage 2633 that iscoaxial with second-coupling-element-main-body passage 2631. Head 1230is shaped so as to define a connecting element 2634 that connectssecond-coupling-element secondary body portion 2632 tosecond-coupling-element main body portion 2630. Head 1230 is shaped soas to define a second-coupling-element space 2635 between main bodyportion 2630 and secondary body portion 2632.

As shown in FIGS. 21 (section A-A, closed position) and in FIGS. 22A-B,first coupling 1220 and head 1230 are coupled together in order toreversibly couple torque-delivering tool 1204 to anchor 40. In such aclosed position, (1) first-coupling-element secondary body portion 2622fits within second-coupling-element space 2635 of head 1230, and (2)second-coupling-element secondary body portion 2632 fits withinfirst-coupling-element space 2625 of first coupling 1220. In such amanner of these fittings, first-coupling-element-main-body passage 2621,first-coupling-element-secondary-body-portion passage 2623,second-coupling-element-main-body passage 2631, andsecond-coupling-element-secondary-body-portion passage 2633 are alignedalong axis 2611.

In order to maintain such coupling of first coupling 1220 and head 1320,an elongate longitudinal element 2610 (e.g., a rod) is reversiblydisposed within first-coupling-element-main-body passage 2621,first-coupling-element-secondary-body-portion passage 2623,second-coupling-element-main-body passage 2631, andsecond-coupling-element-secondary-body-portion passage 2633.

As shown in FIG. 22C, elongate longitudinal element 2610 is removed fromwithin the passages of coupling 1220 and of head 1230 in order tofacilitate decoupling of coupling 1220 from head 1230.

FIG. 21 (section A-A, open position) and FIGS. 22C-D show coupling 1220and head 1230 decoupled from each other. This is accomplished when (1)first-coupling-element secondary body portion 2622 is removed fromsecond-coupling-element space 2635 of head 1230, and (2)second-coupling-element secondary body portion 2632 is removed fromfirst-coupling-element space 2625 of coupling 1220. This decoupling maybe accomplished by tilting tool 1204 away from axis 2611.

Reference is again made to FIG. 21. A proximal end portion 2615 of firstlongitudinal member 2612 is coupled to (e.g., by being looped around) aportion of a first flexible-longitudinal-member-coupling element 2614.First flexible-longitudinal-member-coupling element 2614 is shaped so asto define a threaded coupling for receiving a screw 2618 that is coupledto a distal end of a flexible longitudinal guide member 2616.

When in the closed position (shown in FIG. 21, Section A-A), tool 1204is coupled to anchor 40 and facilitates advancement of anchor 40 towardfirst implantation site 30. As the physician advances tool 2602, thephysician also advances snare 2606. Under imaging guidance,torque-delivering tool 1204 and anchor 40 are advanced through loop 2608of snare 2606, in order to create a coupling between snare 2606 andguide member 2616.

As shown in FIG. 21, torque-delivering tool 1204 is advanced within alumen of tool 2602 alongside first longitudinal member 2612 and guidemember 2616. Torque-delivering tool 1204 is then rotated in order toimplant anchor 40 in cardiac tissue at implantation site 30. Asdescribed hereinabove annular loop 1246 (shown in section A-A)facilitates rotation of anchor 40 with respect to (and not facilitatingrotation of) connecting element 1240, first longitudinal member 2612,first flexible-longitudinal-member-coupling element 2614, and guidemember 2616.

Following implantation of anchor 40 at site 30, tool 1204 is decoupledfrom anchor 40, as described hereinabove, such that the open position isassumed (section A-A, FIG. 21). Torque-delivering tool 1204 is thenretracted through delivery tool 2602. Alternatively, tool 1204 isretracted at a later stage together with delivery tool 2602.

FIG. 23 shows snare 2606, via loop 2608, pulling guide member 2616 indirection A toward inferior vena cava 8. As guide member 2616 is pulled,the proximal portion of guide member 2616 slides in direction A out ofdelivery tool 2602.

As shown in the enlarged image of FIG. 23, firstflexible-longitudinal-member-coupling element 2614 is shaped so as todefine a loop 2646 through which proximal end portion 2615 of firstflexible member 2612 is looped, thereby coupling member 2612 to element2614. End portion 2615 is sewn to itself to maintain the loopedcoupling. As shown, element 2614 is shaped so as to define a malecoupling shaped so as to provide one or more protrusions 2640 (e.g., anannular protrusion, as shown). Protrusion 2640 is shaped so as toprovide a distal shelf 2642 (e.g., an annular shelf), which is describedhereinbelow.

A proximal end of element 2614 is shaped to as to provide a threadedcoupling 2644 which facilitates screwing of a screw 2618 coupled to thedistal end of guide member 2616, as shown.

For some applications (configuration not shown), the distal end of guidemember 2616 may be coupled to first coupling 1220 (described hereinabovewith reference to FIGS. 21 and 22A-D), and a proximal end of element2614 may be coupled to adapter head 1230 (described hereinabove withreference to FIGS. 21 and 22A-D; configuration not shown, but shown inFIG. 28). For such applications, reversible coupling of guide member2616 to element 2614 is accomplished via coupling of coupling 1220 tohead 1230. As described hereinabove, the coupling of coupling 1220 andhead 1230 is maintained by elongate longitudinal element 2610 (describedhereinabove with reference to FIGS. 21 and 22A-D).

FIG. 24 shows guide member 2616 disposed within inferior vena cava 8following the pulling of member 2616 therethrough via snare 2606. Asecond-tissue-engaging-element delivery tool 2666 is then threaded overa proximal portion of guide member 2616 in order to advance a secondtissue-engaging element, a second flexible longitudinal member, and asecond flexible-longitudinal-member-coupling element toward valve 4 fromdirection A.

FIG. 25 shows the advancement of delivery tool 2666 through inferiorvena cava 8. An advancement tube 2667 is advanced through a lumen oftool 2666 and is reversibly coupled at a distal end thereof to a secondflexible-longitudinal-member-coupling element 2650. Secondflexible-longitudinal-member-coupling element 2650 defines a femalecoupling element that is shaped so as to define a cylindrical element,in such applications, which receives the male coupling element ofelement 2614. Element 2650 and tube 2667 slide along guide member 2616in order to couple together second flexible-longitudinal-member-couplingelement 2650 and first flexible-longitudinal-member-coupling element2614.

Element 2650 is shaped so as to define one or more tabs 2652 biased toflex toward a longitudinal axis 2656 of the cylinder of element 2650. Ascoupling element 2650 slides over the male coupling of element 2614, theprotrusion 2640 of the male coupling of element 2614 is advanceable withrespect to the one or more tabs 2652 in a first direction (e.g., aproximal direction) to push tab 2652 away from longitudinal axis 2656.Element 2614 is shaped so as to define a section distal to protrusion2640 that is narrower than protrusion 2640. After protrusion 2640advances beyond tab 2652, tab 2652 assumes its resting position in whichit flexes toward axis 2656 and closes around the narrower portion distalto protrusion 2640, as shown in Section A-A. Shelf 2642 of protrusion2640 has a dimension that is larger than a dimension of tab 2652 in itsresting state and restricts advancement of the male coupling of element2614 in a second direction (e.g., a distal direction). In such a manner,tabs 2652, protrusion 2640, and shelf 2642 lock element 2614 withrespect to element 2650.

As shown, element 2650 is shaped so as to define one or more grooves2657. For some applications, protrusion 2640 fits within the one or moregrooves 2657 in order to couple together elements 2650 and 2614. Asshown, a distal portion 2662 of longitudinal member 2660 is loopedaround a looping portion 2654 of element 2650.

Following the coupling of elements 2650 and 2614, tube 2667 is decoupledfrom element 2650. Additionally, guide member 2616 is decoupled fromelement 2614 by being unscrewed therefrom (as shown by the arrow insection A-A).

Second flexible longitudinal member 2660 is coupled at a distal portionthereof to a proximal portion of secondflexible-longitudinal-member-coupling element 2650, e.g., by beinglooped around a portion of element 2650, as shown.

Following decoupling of guide member 2616, first and second couplingelements 2614 and 2650, respectively, remain coupled together andthereby couple together first and second longitudinal members 2612 and2660, respectively.

After elements 2614 and 2650 are coupled together, tool 2666 isretracted through inferior vena cava 8 in order apply tension toflexible members 2612 and 2660 and thereby to first tissue-engagingelement 60 a, as described hereinabove, in order to adjust a distancebetween the leaflets of tricuspid valve 4 to reduce and eliminateregurgitation through valve 4, and thereby, to repair valve 4.

In FIG. 26, second tissue-engaging element 60 b comprising stent 50 isthen deployed in inferior vena cava 8 so as to ensure that tension ismaintained at first implantation site 30 and along longitudinal members2612 and 2660 (i.e., longitudinal members 42). Stent 50 is coupled to aproximal portion of longitudinal member 2660. The positioning of stent50 along inferior vena cava 8 depends on the desired degree of tensionof members 2612 and 2660 and on site 30 and of the desired degree ofrepair of valve 4.

It is to be noted that any one of stents 1150, 1400, and 1500 describedhereinabove may be used in place of any one of stents 50.

Reference is now made to FIGS. 20-26. It is to be noted that thedirection of implantation of elements 60 a and 60 b may be opposite tothose as shown in FIGS. 20-26. For example, element 60 a may beimplanted in tissue of valve 4 by being advanced through inferior venacava 8, and element 60 b may be implanted in superior vena cava 10.

Reference is now made to FIG. 27, which is a schematic illustration of aflexible-longitudinal-member-adjustment mechanism 2670 which is coupledto flexible member 2660 in order to adjust a length and/or degree oftension of member 2660, in accordance with some applications of thepresent invention. For some applications, mechanism 2670 comprises aspool (not shown) configured to adjust the length/tension of member 2660by winding a portion of member 2660 around the spool. For someapplications, adjustment mechanism 2670 is coupled to first flexiblelongitudinal member 2612.

An adjustment-mechanism tool 2672 is reversibly coupled to mechanism2670. As shown, tool 2672 is coupled at a distal end thereof to firstcoupling 1220 (described hereinabove with (described hereinabove withreference to FIGS. 21 and 22A-D), and adjustment mechanism 2670 iscoupled to adapter head 1230 (described hereinabove with reference toFIGS. 21 and 22A-D). For such applications, reversible coupling of tool2672 to mechanism 2670 is accomplished via coupling of coupling 1220 tohead 1230. As described hereinabove, the coupling of coupling 1220 andhead 1230 is maintained by elongate longitudinal element 2610 (describedhereinabove with reference to FIGS. 21 and 22A-D).

Flexible-longitudinal-member-adjustment mechanism 2670 may be used incombination with system 2600 described herein with reference to FIGS.20-26 and 28-32. Additionally, mechanism 2670 may be used in combinationwith systems 20, 100, 110, 120, 140, 200, 700, 800, 1000, and/or 2500.

Reference is now made to FIG. 28, which is a schematic illustration of(1) first flexible-longitudinal-member-coupling element 2614 comprisingone or more (e.g., two, as shown) radially-displaceable arms 2684, and(2) second flexible-longitudinal-member-coupling element 2650 having oneor more walls 2682 shaped so as to define an opening 2680, in accordancewith some applications of the present invention. Opening 2680 has adimension 2688.

A proximal end of element 2614 is coupled to adapter head 1230(described hereinabove with reference to FIGS. 21 and 22A-D), or alongitudinal-guide-member-coupling element. For such applications, guidemember 2616 (not shown) is coupled at a distal end thereof to firstcoupling 1220 (described hereinabove with reference to FIGS. 21 and22A-D) and is coupled to element 2614 via couplings 1220 and head 1230.It is to be noted that guide member 2616 may also be coupled to element2614 by being screwed into a threaded coupling 2644 of element 2614, asdescribed hereinabove with reference to FIGS. 21, 23, and 25.

In either embodiment, second flexible-longitudinal-member-couplingelement 2650 is slid over the guide member until opening 2680 is alignedwith arms 2684 of element 2614. Element 2650 is further slid distallyalong element 2614 such that wall 2682 compresses arms 2684 throughopening 2680. Once element 2650 is slid further, at is 2685 are exposedfrom within opening 2680 and expand to a position that is above opening2680. Arms 2684 expand to a dimension 2686 that is larger than dimension2688 of opening 2680. Arms 2684 expand to a position in which at least aportion of respective outer surfaces 2685 of arms 2684 is beyond andabove wall 2682. In such a manner, arms 2684 lock element 2614 toelement 2650, and thereby maintain coupling of flexible members 2612 and2660.

Reference is now made to FIGS. 29 and 30A-D, which are schematicillustrations of (1) first flexible-longitudinal-member-coupling element2614 comprising one or more radially-displaceable legs 2694 (e.g., two,as shown), and (2) second flexible-longitudinal-member-coupling element2650 having one or more walls 2691 (FIG. 30A) shaped so as to define anopening 2693 and one or more shelves 2692 (e.g., an annular shelf), inaccordance with some applications of the present invention.

In such applications, the female coupling is coupled to first flexiblelongitudinal member 2612, and the male coupling is coupled to secondflexible longitudinal member 2660.

As shown in FIGS. 30A-B, guide member 2616 is coupled at a distal endthereof to a guide-member-coupling element 2690 (e.g., a disc, asshown). At a fist stage, element 2690 is restricted from movement in aproximal direction by shelf 2692 of element 2560. In such a manner,guide member 2616 is reversibly coupled to element 2650.

As shown in FIGS. 29 and 30A, element 2614 is shaped so as to define acylinder having a lumen, and is guided along guide member 2616 towardelement 2614.

In FIG. 30B a distal end of element 2614 and legs 2694 are advanced in afirst direction (e.g., a distal direction) within a lumen of element2650, and legs 2694 approach opening 2693. As they approach opening2693, legs 2694 are compressed by wall 2691 and by shelf 2692. Followingthe advancement of legs 2694 beyond shelf 2692 in the first advancementdirection, legs 2694 are expandable to lock element 2614 to element2650. Additionally, following the expanding of legs 2694, shelf 2692restricts advancement of legs 2694 in a second advancement direction(e.g., a proximal direction) since legs 2694 expand to a dimensionlarger than a dimension of shelf 2692.

Additionally, the positioning of legs 2694 beyond shelf 2692 displacesguide-member-coupling element 2690, as shown in FIG. 30C. Thedisplacement of element 2690 shifts the relative position of element2690 with respect to shelf 2692 of element 2650, and element 269 may beadvanced in the second direction (e.g., the proximal direction) throughand beyond opening 2693.

FIG. 30D shows the decoupling of element 2690 and guide member 2616 fromelement 2650 and subsequently, from element 2614. As shown, elements2614 and 2650 are locked together by the positioning of the distalportion of legs 2694 distally to shelf 2692.

Wall 2691 of element 2650 is shaped so as to define at least one groove2697. As shown in FIG. 29, element 2614 is shaped so as to define atleast one protrusion 2698 (e.g., an annular protrusion, as shown), whichis shaped so as to fit within the at least one groove 2697. Thepositioning of protrusion 2698 within groove 2697, as shown in FIGS.30C-D, further locks elements 2614 and 2650.

Reference is now made to FIG. 31, which is a schematic illustration of(1) first flexible-longitudinal-member-coupling element 2614 comprisingone or more protrusions 2702, and (2) secondflexible-longitudinal-member-coupling element 2650 being shaped so as todefine one or curved grooves 2700, in accordance with some applicationsof the present invention. Guide member 2616 is reversibly coupled toelement 2650 using any of the coupling apparatus described herein withreference to FIGS. 21, 22A-C, 23, 25, 28, 29, 30A-D, and 32.

As shown in view A, element 2614 is advanced along guide member 2616toward element 2650. In view B, protrusion 2702 of element 2614 ispositioned within a portion of curved groove 2700. In view C, element2614 is rotated in order to position and lock protrusion 2702 withingroove 2700 at an end of groove 2700. In such a manner, element 2614 islocked to element 2650. Following the locking of elements 2614 and 2650,guide member 2616 is decoupled from element 2650.

FIG. 32 shows guide member 2616 being coupled to element 2614 by bringlooped around a bar 2720 coupled to element 2614, in accordance withsome applications of the present invention. In such an application,element 2650 defines the female coupling which is advanced along guidemember 2616 toward element 2614, which defines the male coupling. Onceelement 2650 is coupled to element 2614, a first end of looped guidemember 2616 is released, and the second end of guide member 2616 ispulled in order to unloop guide member 2616 from around bar 2720, andthereby to decouple guide member 2616 from element 2614.

Reference is now made to FIGS. 28, 29, 31, and 32. It is to be notedthat although stent 50 is shown as comprising stent 1400, any one ofstents 1150 and 1500 may be used in place of any one of stents 1400.

Reference is now made to FIGS. 20-32. The scope of the present inventionincludes coupling of element 2614 to either of longitudinal members 2612and 2660 and coupling of element 2650 to either of longitudinal members2612 and 2660.

Reference is now made to FIGS. 1A-D, 2A-B, 3A-C, 4A-C, 5A-B, 6, 7A-D, 8,9, 10A-D, 11A-C, 12A-C, 13A-C, 14A-C, 15A-B, 16A-B, 17, 18A-B, and19-32. It is to be noted that apparatus and methods described herein forrepairing tricuspid valve 4 may also be applied to repair any otherheart valve of the patient, e.g., a mitral valve, a pulmonary valve, oran aortic valve. For such applications, second implantation site 52 mayinclude a portion of a blood vessel that is in contact with the leftatrium of the patient, e.g., a pulmonary vein, a portion of the wall ofthe left atrium, a portion of the annulus of the mitral valve, or aportion of the left ventricle of the heart of the patient, and firstimplantation site 30 may include a portion of the wall of the leftatrium, a portion of the annulus of the mitral valve, or a portion ofthe left ventricle of the heart of the patient.

Reference is again made to FIGS. 1A-D, 2A-B, 3A-C, 4A-C, 5A-B, 6, 7A-D,8, 9, 10A-D, 11A-C, 12A-C, 13A-C, 14A-C, 15A-B, 16A-B, 17, 18A-B, and19-32. It is to be noted that any one of stents 1150, 1400, and 1500 maybe used in place of any one of stents 50 shown in FIGS. 1D, 2A-B, 3A-C,4B-C, 6, 7A-D, 8, 9, 16A-B, and 17. It is to be further noted thatsystem 1000 shown in FIGS. 11A-C and 12A-C may be used to implant anytissue anchor 40 described herein and stent 50 described herein.Specifically, system 1000 shown in FIGS. 11A-C and 12A-C may be used inplace of system 200, as described hereinabove with reference to FIGS.7A-D.

Reference is yet again made to FIGS. 1A-D, 2A-B, 3A-C, 4A-C, 5A-B, 6,7A-D, 8, 9, 10A-D, 11A-C, 12A-C, 13A-C, 14A-C, 15A-B, 16A-B, 17, 18A-B,and 19-32. It is to be noted that any suitable number of tissue-engagingelements 60 may be implanted in and/or grasp cardiac tissue, dependingon the needs of a given patient. Typically, one or more tissue-engagingelements 60 is/are implanted in cardiac tissue (e.g., tissue of theannulus, tissue of the wall of the atrium adjacent the valve, or tissueof the wall of the ventricle adjacent the valve) in a vicinity of thevalve that is between the middle of the anterior leaflet and the middleof the posterior leaflet, e.g., at the commissure between the middle ofthe anterior leaflet and the middle of the posterior leaflet. For suchan application, pulling together implantation sites 30 and 52 pullsanterior leaflet 14 toward septal leaflet 12 and thereby achievesbicuspidization of tricuspid valve 4. It is to be noted, however, thattissue-engaging elements 60 may be implanted in portions of tissue inthe vicinity of any portion of the annulus of valve 4.

Reference is still yet again made to FIGS. 1A-D, 2A-B, 3A-C, 4A-C, and5A-B, 6, 7A-D, 8, 9, 10A-D, 11A-C, 12A-C, 13A-C, 14A-C, 15A-B, 16A-B,17, 18A-B, and 19-32. It is to be noted that the adjustment of thedistance between the respective implantation sites of thetissue-engaging elements 60 is facilitated by adjusting mechanism 150following initial implantation of the tissue-engaging elements 60 andthe repair of the valve and/or the adjustment of the heart wallgeometry.

It will be appreciated by persons skilled in the art that the presentinvention is not limited to what has been particularly shown anddescribed hereinabove. Rather, the scope of the present inventionincludes both combinations and subcombinations of the various featuresdescribed hereinabove, as well as variations and modifications thereofthat are not in the prior art, which would occur to persons skilled inthe art upon reading the foregoing description.

1-75. (canceled)
 76. Apparatus, comprising: a first tissue-engaging element; a first flexible longitudinal member coupled at a first end portion thereof to at least a portion of the first tissue-engaging element; a first flexible-longitudinal-member-coupling element coupled to the first flexible longitudinal member at a second end portion of the first flexible longitudinal member; a second tissue-engaging element; a second flexible longitudinal member coupled at a first end portion thereof to at least a portion of the second tissue-engaging element; and a second flexible-longitudinal-member-coupling element coupled to the second flexible longitudinal member at a second end portion of the second flexible longitudinal member, the first and second flexible-longitudinal-member-coupling elements being couplable to couple together the first and second flexible longitudinal elements.
 77. (canceled)
 78. The apparatus according to claim 76, further comprising a connecting element coupled to the first tissue-engaging element, the connecting element shaped so as to provide an annular loop surrounding a proximal portion of the first tissue-engaging element in a manner which enables rotation of the anchor about the central longitudinal axis when surrounded by the annular loop, wherein the annular loop of the connecting element facilitates rotation of the first tissue-engaging element about a central longitudinal axis of the first tissue-engaging element such that the first tissue-engaging element can rotate about the central longitudinal axis with respect to the annular loop and the first flexible longitudinal member.
 79. The apparatus according to claim 76, further comprising a flexible-longitudinal-member-adjustment mechanism coupled to a flexible longitudinal member selected from the group consisting of: the first flexible longitudinal member and the second flexible longitudinal member, and wherein the flexible-longitudinal-member-adjustment mechanism is configured to adjust a length of the selected flexible longitudinal member.
 80. The apparatus according to claim 79, wherein the flexible-longitudinal-member-adjustment mechanism comprises a spool configured to adjust a length of the selected flexible longitudinal member by winding a portion of the selected flexible longitudinal member around the spool.
 81. The apparatus according to claim 76, wherein the first tissue-engaging element comprises a tissue anchor configured to penetrate tissue of an annulus of an atrioventricular valve of a patient.
 82. The apparatus according to claim 81, wherein the second tissue-engaging element comprises a radially-expandable percutaneous implant configured to engage tissue of the patient upstream of the atrioventricular valve.
 83. (canceled)
 84. The apparatus according to claim 81, wherein the tissue anchor comprises a helical tissue anchor, and wherein the apparatus further comprises a torque-delivering tool configured to corkscrew the helical tissue anchor into tissue of a patient.
 85. The apparatus according to claim 84, further comprising a connecting element shaped to define an annular loop surrounding a proximal portion of the tissue anchor, in a manner which enables rotation of the anchor about a longitudinal axis of the tissue anchor, when surrounded by the annular loop, and with respect to the first flexible longitudinal member.
 86. The apparatus according to claim 76, wherein: the apparatus further comprises a first coupling element coupled to the first tissue-engaging element, the first coupling element having a first-coupling-element longitudinal axis and shaped so as to define: a first-coupling-element main body portion shaped so as to define a first-coupling-element-main-body passage, a first-coupling-element secondary body portion coaxial with the first-coupling-element main body portion, the first-coupling element secondary body portion shaped so as to define a first-coupling-element-secondary-body-portion passage coaxial with the first-coupling-element-main-body passage; and a connecting element connecting the first-coupling-element secondary body portion to the first-coupling-element main body portion, the first coupling element is shaped so as to define a first-coupling-element space between the first-coupling-element main body portion and the first-coupling-element secondary body portion, the apparatus further comprises a second coupling element having a second-coupling-element longitudinal axis and shaped so as to define: a second-coupling-element main body portion shaped so as to define second-coupling-element-main-body passage, a second-coupling-element secondary body portion coaxial with the main body portion, the second-coupling-element secondary body portion shaped so as to define a second-coupling-element-secondary-body-portion passage coaxial with the second-coupling-element-main-body passage, and a connecting element connecting the second-coupling-element secondary body portion to the second-coupling-element main body portion, the second coupling element is shaped so as to define a second-coupling-element space between the main body portion and the secondary body portion, and the first and second coupling elements are couplable together by fitting the first-coupling-element secondary body portion within the second-coupling-element space of the second coupling element, and by fitting the second-coupling-element secondary body portion within the first-coupling-element space of the first coupling element in a manner in which the first-coupling-element-main-body passage, the first-coupling-element-secondary-body-portion passage, the second-coupling-element-main-body passage, and the second-coupling-element-secondary-body-portion passage are aligned, and the apparatus further comprises an elongate longitudinal element: disposable within the first-coupling-element-main-body passage, the first-coupling-element-secondary-body-portion passage, the second-coupling-element-main-body passage, and the second-coupling-element-secondary-body-portion passage to maintain coupling of the first coupling element to the second coupling element, and removable from the first-coupling-element-main-body passage, the first-coupling-element-secondary-body-portion passage, the second-coupling-element-main-body passage, and the second-coupling-element-secondary-body-portion passage to facilitate decoupling of the first and second coupling elements. 87-89. (canceled)
 90. The apparatus according to claim 76, wherein the first flexible-longitudinal-member-coupling element comprises a male coupling, and wherein the second flexible-longitudinal-member-coupling element comprises a female coupling configured to receive the male coupling.
 91. (canceled)
 92. The apparatus according to claim 90, wherein: the female coupling comprises a cylinder configured to receive the male coupling, the female coupling is shaped so as to define one or more tabs biased to flex toward a longitudinal axis of the cylinder, the male coupling is shaped so as to provide one or more protrusions defining a shelf, the male coupling advanceable with respect to the one or more tabs in a first direction to push the tab away from the longitudinal axis, and the one or more tabs are configured to flex toward the longitudinal axis after the advancement of the shelf of the male coupling beyond the one or more tabs to restrict advancement of the male coupling in a second direction.
 93. The apparatus according to claim 90, wherein: the female coupling comprises a structural element comprising one or more walls shaped so as to define an opening, the male coupling comprises one or more radially-displaceable arms, and the one or more radially-displaceable arms are: compressible by the walls during advancement of the one or more radially-displaceable arms through the opening, and following advancement of the one or more radially-displaceable arms through opening, expandable to a first dimension that is larger than a second dimension of the opening so as to lock the male coupling to the female coupling.
 94. The apparatus according to claim 90, wherein: the female coupling comprises a structural element comprising one or more walls shaped so as to define an opening, the male coupling comprises one or more radially-displaceable arms, and the one or more radially-displaceable arms are: compressible by the walls during advancement of the one or more radially-displaceable arms through the opening, and following advancement of the one or more radially-displaceable arms through opening, expandable to a position in which at least a portion of an outer surface of the one or more arms is beyond and above the one or more walls.
 95. The apparatus according to claim 90, wherein: the female coupling comprises a structural element comprising one or more walls shaped so as to define one or more shelves, the male coupling comprises one or more radially-displaceable legs, the one or more radially-displaceable legs are: compressible by the walls during advancement of the one or more radially-displaceable legs along the one or more shelves, and following the advancement of the one or more radially-displaceable legs beyond the one or more shelves in a first advancement direction, expandable to lock the male coupling to the female coupling, and following expanding of the one or more radially-displaceable legs, the one or more shelves of the female coupling restrict advancement of the one or more radially-displaceable legs in a second advancement direction.
 96. The apparatus according to claim 95, wherein the one or more walls of the female coupling element is shaped so as to define at least one groove, and wherein the male coupling element is shaped so as to define at least one protrusion shaped so as to fit within the at least one groove.
 97. The apparatus according to claim 76, wherein the female coupling comprises a structural element shaped so as to define a curved groove, and wherein the male coupling comprises a projection advanceable within the curved groove so as to lock the male coupling to the female coupling.
 98. The apparatus according to claim 76, wherein the apparatus further comprises a flexible longitudinal guide member reversibly coupled to the first flexible-longitudinal-member-coupling element.
 99. The apparatus according to claim 98, wherein the flexible longitudinal guide member is reversibly coupled to the first flexible-longitudinal-member-coupling element by being looped through a portion of the first flexible-longitudinal-member-coupling element.
 100. The apparatus according to claim 98, wherein: the first flexible-longitudinal-member-coupling element is shaped so as to define a first coupling, the flexible longitudinal guide member is reversibly coupled to the first flexible-longitudinal-member-coupling element via the first coupling, and the flexible longitudinal guide member is configured to facilitate advancement of the second flexible-longitudinal-member-coupling element along the guide member and toward the first flexible-longitudinal-member-coupling element.
 101. The apparatus according to claim 100, further comprising a snare couplable to the flexible longitudinal guide member so as to facilitate extraction of a portion of the guide member outside a body of a patient.
 102. The apparatus according to claim 101, wherein: the first tissue-engaging element, the first flexible longitudinal member, and the first flexible-longitudinal-member-coupling element are advanceable within the body of that patient from a first site thereof, the second tissue-engaging element, the second flexible longitudinal member, and the second flexible-longitudinal-member-coupling element are advanceable within the body of that patient from a second site thereof, and the snare is configured to extend a portion of the flexible longitudinal guide member toward the second site.
 103. The apparatus according to claim 100, wherein the first coupling comprises a threaded coupling, and wherein the flexible longitudinal guide member is reversibly coupled to the first coupling by being screwed with respect to the threaded coupling.
 104. The apparatus according to claim 100, wherein the first coupling is shaped so as to define at least one shelf, and wherein the apparatus further comprises a longitudinal-guide-member-coupling element, wherein the longitudinal-guide-member-coupling element is: coupled to the longitudinal guide member, restricted from advancement in a first direction by the at least one shelf, and displaceable with respect to the at least one shelf in response to a change in a spatial orientation of the longitudinal-guide-member-coupling element with respect to the at least one shelf, and allowed to advance in the first direction in order to decouple the longitudinal guide member from the first flexible-longitudinal-member-coupling element.
 105. The apparatus according to claim 100, wherein: the first flexible-longitudinal-member-coupling element has a first-coupling-element longitudinal axis and wherein the first coupling is shaped so as to define: a first-coupling-element main body portion shaped so as to define first-coupling-element-main-body passage; a first-coupling-element secondary body portion coaxial with the main body portion, the first-coupling element secondary body portion shaped so as to define a first-coupling-element-secondary-body-portion passage coaxial with the first-coupling-element-main-body passage; and a connecting element connecting the secondary body portion to the main body portion, the first flexible-longitudinal-member-coupling element is shaped so as to define a first-coupling-element space between the main body portion and the secondary body portion, the apparatus further comprises a longitudinal-guide-member-coupling element having a longitudinal-guide-member-coupling element longitudinal axis and a second coupling, wherein the flexible longitudinal guide member coupled to the longitudinal-guide-member-coupling element, and is reversibly coupled to the first flexible-longitudinal-member-coupling element via the longitudinal-guide-member-coupling element, the second coupling being shaped so as to define: a longitudinal-guide-member-coupling-element main body portion shaped so as to define second-coupling-element-main-body passage; a longitudinal-guide-member-coupling-element secondary body portion coaxial with the main body portion, the longitudinal-guide-member-coupling-element secondary body portion shaped so as to define a longitudinal-guide-member-coupling element-secondary-body-portion passage coaxial with the longitudinal-guide-member-coupling-element-main-body passage; and a connecting element connecting the longitudinal-guide-member-coupling-element secondary body portion to the longitudinal-guide-member-coupling-element main body portion, the second coupling element is shaped so as to define a second-coupling-element space between the main body portion and the secondary body portion, and the first and second couplings are couplable together by fitting the first-coupling-element secondary body portion within the longitudinal-guide-member-coupling-element space of the second coupling element, and by fitting the longitudinal-guide-member-coupling-element secondary body portion within the first-coupling-element space of the first coupling element in a manner in which the first-coupling-element-main-body passage, the first-coupling-element-secondary-body-portion passage, the longitudinal-guide-member-coupling-element-main-body passage, and the longitudinal-guide-member-coupling-element-secondary-body-portion passage are aligned.
 106. The apparatus according to claim 105, wherein the apparatus further comprises an elongate longitudinal element: disposable within the first-coupling-element-main-body passage, the first-coupling-element-secondary-body-portion passage, the longitudinal-guide-member-coupling-element-main-body passage, and the longitudinal-guide-member-coupling-element-secondary-body-portion passage to maintain coupling of the first and second couplings, and removable from the first-coupling-element-main-body passage, the first-coupling-element-secondary-body-portion passage, the longitudinal-guide-member-coupling-element-main-body passage, and the longitudinal-guide-member-coupling-element-secondary-body-portion passage to facilitate decoupling of the first and second couplings.
 107. A method, comprising: implanting a first tissue-engaging element at a first implantation site in tissue of an atrioventricular valve of a patient; extending from the first tissue-engaging element, a first flexible longitudinal member coupled at a first end portion thereof to at least a portion of the first tissue-engaging element, the first flexible longitudinal element being coupled at a second end portion thereof to a first flexible-longitudinal-member-coupling element; advancing toward the valve of the patient a second tissue-engaging element coupled to a first end portion of a second flexible longitudinal member, the second flexible longitudinal member being coupled at a second end portion thereof to a second flexible-longitudinal-member-coupling element; coupling together the first and second flexible-longitudinal-member-coupling elements; facilitating repairing of the atrioventricular valve by pulling on the second tissue-engaging element, and responsively, pulling on the first and second flexible longitudinal members; and implanting the second tissue-engaging element at a second implantation site upstream of the atrioventricular valve.
 108. The method according to claim 107, wherein facilitating repairing comprises remodeling the atrioventricular valve by drawing together leaflets of the valve responsively to the pulling. 109-125. (canceled) 